+
МАТЕМАТИЧЕСКОЕ МОДЕЛИРОВАНИЕ РАСПРОСТРАНЕНИЯ ПЛАМЕНИ В ВОДОРОД-ВОЗДУШНЫХ СМЕСЯХ
стр.5-16
Беляев П.Е., Аетпаева М.С., Ковалев Ю.М., Пигасов Е.Е.
Развитие водородной энергетики неразрывно связано с обеспечением водородной безопасности и исследованием процессов, протекающих при горении водород-содержащих смесей. Использование численного моделирования позволяет исследовать поведение системы в диапазонах изменения основных параметров, не покрытых экспериментальными данными. В данной работе представлена модель, позволяющая моделировать течения химически реагирующих сплошных сред, верифицированная на экспериментальных данных по распространению пламени в ударной трубе с перегородками, заполненной водород-воздушной смесью.
Загружаем данные из библиотечной системы...
Ключевые слова
+
STABILITY OF SOLUTIONS TO THE STOCHASTIC OSKOLKOV EQUATION AND STABILIZATION
стр.17-26
This paper studies the stability of solutions to the stochastic Oskolkov equation describing a plane-parallel flow of a viscoelastic fluid. This is the equation we consider in the form of a stochastic semilinear Sobolev type equation. First, we consider the solvability of the stochastic Oskolkov equation by the stochastic phase space method. Secondly, we consider the stability of solutions to this equation. The necessary conditions for the existence of stable and unstable invariant manifolds of the stochastic Oskolkov equation are proved. When solving the stabilization problem, this equation is considered as a reduced stochastic system of equations. The stabilization problem is solved on the basis of the feedback principle; graphs of the solution before stabilization and after stabilization are shown.
Загружаем данные из библиотечной системы...
Ключевые слова
+
INVARIANT DESCRIPTION OF CONTROL IN A GAUSSIAN ONE-ARMED BANDIT PROBLEM
стр.27-36
We consider the one-armed bandit problem in application to batch data processing if there are two alternative processing methods with different efficiencies and the efficiency of the second method is a priori unknown. During the processing, it is necessary to determine the most effective method and ensure its preferential use. Processing is performed in batches, so the distributions of incomes are Gaussian. We consider the case of a priori unknown mathematical expectation and the variance of income corresponding to the second action. This case describes a situation when the batches themselves and their number have moderate or small volumes. We obtain recursive equations for computing the Bayesian risk and regret, which we then present in an invariant form with a control horizon equal to one. This makes it possible to obtain the estimates of Bayesian and minimax risk that are valid for all control horizons multiples to the number of processed batches.
Загружаем данные из библиотечной системы...
Ключевые слова
+
РЕШЕНИЕ ОБРАТНЫХ ЗАДАЧ ДОСТИЖЕНИЯ СВЕРХРАЗРЕШЕНИЯ ПРИ ИСПОЛЬЗОВАНИИ НЕЙРОННЫХ СЕТЕЙ
стр.37-48
Лаговский Б.А., Насонов И.А., Рубинович Е.Я.
Рассматривается актуальная проблема получения приближенных численных решений обратных задач в виде интегральных уравнений Фредгольма первого рода для систем радио- и гидролокации и дистанционного зондирования. Полученные решения дают возможность существенно повысить точность измерений, а также довести угловую разрешающую способность до значений, превышающих критерий Рэлея. Это позволяет: получать детализированные радиоизображения различных объектов и зондируемых областей; определять количество отдельных малоразмерных объектов в составе сложных целей, которые раздельно не фиксировались без представляемой обработки сигналов; получать координаты таких малоразмерных объектов с высокой точностью; повысить вероятности получения правильных решений задач распознавания и идентификации объектов. Метод применим для современных многоэлементных измерительных систем. Он основан на экстраполяции сигналов, принимаемых всеми элементами, за пределы самой системы. Решена задача создания необходимой для этого нейронной сети и ее обучения. В итоге, синтезируется новая виртуальная измерительная система значительно большего размера, что позволяет резко повысить угловое разрешение и тем самым повысить качество приближенных решений рассматриваемых обратных задач. На примерах демонстрируется эффективность метода, оценивается адекватность и устойчивость получаемых решений. Исследуется степень превышения виртуальной угломерной системой критерия Рэлея в зависимости от отношения сигнал/шум.
Загружаем данные из библиотечной системы...
Ключевые слова
+
INVESTIGATION OF THE UNIQUENESS SOLUTION OF THE SHOWALTER-SIDOROV PROBLEM FOR THE MATHEMATICAL HOFF MODEL. PHASE SPACE MORPHOLOGY
стр.49-63
Nikolaeva N.G., Gavrilova O.V., Manakova N.A.
The study of the phase space morphology of the mathematical model deformation of an I-beam, which lies on smooth Banach manifolds with singularities (k-Whitney assembly) depending on the parameters of the problem, is devoted to the paper. The mathematical model is studied in the case when the operator at time derivative is degenerate. The study of the question of non-uniqueness of the solution of the Showalter-Sidorov problem for the Hoff model in the two-dimensional domain is carried out on the basis of the phase space method, which was developed by G.A. Sviridyuk. The conditions of non-uniqueness of the solution in the case when the dimension of the operator kernel at time derivative is equal to 1 or 2 are found. Two approaches for revealing the number of solutions of the Showalter-Sidorov problem in the case when the dimension of the operator kernel at time derivative is equal to 2 are presented. Examples illustrating the non-uniqueness of the solution of the problem on a rectangle are given.
Загружаем данные из библиотечной системы...
Ключевые слова
+
INFLUENCE TO NEW FORMULAS GRADIENT FOR REMOVING IMPULSE NOISE IMAGES
стр.64-74
Basim A.H., Ali Ahmed A.A.
In conjugate gradient techniques, the conjugate formula is often the primary point of concentration. The conjugate gradient technique is used to solve problems that arise during the process of picture restoration. By using the quadratic model, a brand-new coefficient conjugate will be produced for the operation. The algorithms demonstrate both local and global convergence and descent. The numerical testing revealed that the newly developed method is much superior to the one that came before it. The recently created conjugate gradient strategy has better performance than the FR conjugate gradient technique, which is the industry standard.
Загружаем данные из библиотечной системы...
Ключевые слова
+
TABLE RECOGNITION TECHNOLOGY IN TAX DOCUMENTS OF THE RUSSIAN FEDERATION
стр.75-85
This paper investigates the problem of cell recognition in the image of a table using the example of the Russian tax document (2-NDFL). Despite the simple structure of the tables, the printing method is based on a flexible template. The flexibility of the form is observed in the modifications of textual information and in the table area. The flexibility of tables lies in the modification of the number and size of columns. A structural method was proposed for table detection. The input data are the detected horizontal and vertical segments. Segments were searched by the Smart Document Reader system. Implementing and testing the method were also carried out in the Smart Document Reader system. In addition to detecting the area where tables can be placed, the following objectives were achieved: searching for table cells, naming table cells, and validating the table area. Validation of the table area was performed for separate tables and for table sets. The application of table aggregate descriptions showed the high reliability of linking table sets.
Загружаем данные из библиотечной системы...
Ключевые слова
+
ANALYSIS OF THE WENTZELL STOCHASTIC SYSTEM COMPOSED OF THE EQUATIONS OF UNPRESSURISED FILTRATION IN THE HEMISPHERE AND AT ITS BOUNDARY
стр.86-96
Goncharov N.S., Sviridyuk G.A.
The deterministic and stochastic Wentzell systems of Dzekzer equations in a hemisphere and on its boundary are studied for the first time. The deterministic case is characterised by the unambiguous solvability of the initial problem for the Wentzell system in a specific constructed Hilbert space. In the case of the stochastic hydrodynamic system ``reservoir-well-collector'', the theory of Nelson-Glicklich derivative is applied and a stochastic solution is constructed, which allows us to determine the prognoses of quantitative changes in the geochemical regime of groundwater under non-pressure filtration. It should be noted that for the filtration system under study, the non-classical Wentzell condition is considered, since it is represented by an equation with the Laplace - Beltrami operator defined on the boundary of the domain, understood as a smooth compact Riemannian manifold without an edge, and the external influence is represented by the normal derivative of the function defined in the domain.
Загружаем данные из библиотечной системы...
Ключевые слова
+
INVESTIGATION OF THE TRANSIENT RESPONSES OF A BEAM ON AN ELASTIC POLYMERIC FOUNDATION
стр.97-105
Kashcheeva A.D., Zamyshlyaeva A.A.
The negative impact of vibrations on various devices and mechanisms can be significant, so it is important to take this factor into account when designing, operating and maintaining various equipment and engineering systems. Various methods and technologies can be used to protect against the negative effects of vibrations. Special damping materials are often used. This research paper is devoted to the analysis of the effectiveness of vibration reduction taking into account the physical parameters of elastic polymeric materials. To conduct the study, a mathematical model describing motion of the beam resting on an elastic polymeric foundation is constructed. The model is based on a system of nonlinear differential equations. An algorithm was developed and applied for the numerical solution of this system of equations. Numerical experiments were carried out for the study of the system reaction to different cases of accelerations. As a result, the deflection structure for materials with different physical characteristics were obtained. These results can serve as a starting point for a deeper study of materials and creation of more complex structures.
Загружаем данные из библиотечной системы...
Ключевые слова
+
ЮРИЙ ЕВГЕНЬЕВИЧ ГЛИКЛИХ (К 75-ЛЕТИЮ СО ДНЯ РОЖДЕНИЯ)
стр.106-108
Редакционная коллегия и редакционный совет журнала
Загружаем данные из библиотечной системы...
