Izvestiya of Saratov University Mathematics Mechanics Informatics最新文献_第9页

Resource optimization in management of technical maintenance of automation and remote control systems 自动化和远程控制系统技术维护管理中的资源优化

IF 0.2

Izvestiya of Saratov University Mathematics Mechanics Informatics Pub Date : 2021-08-25 DOI: 10.18500/1816-9791-2021-21-3-379-389

A. V. Gorelik, A. V. Orlov, D. V. Speranskiy

引用次数: 0

Differential operators on graphs with a cycle 循环图上的微分算子

IF 0.2

Izvestiya of Saratov University Mathematics Mechanics Informatics Pub Date : 2021-08-25 DOI: 10.18500/1816-9791-2021-21-3-343-351

V. Yurko

引用次数: 0

The explicit solution of the Neumann boundary value problem for Bauer differential equation in circular domains 圆域上Bauer微分方程的Neumann边值问题的显式解

IF 0.2

Izvestiya of Saratov University Mathematics Mechanics Informatics Pub Date : 2021-08-25 DOI: 10.18500/1816-9791-2021-21-3-326-335

K. .. Rasulov, T. R. Nagornaya

引用次数: 0

Construction of 3D solid vertebral models using convolutional neural networks 利用卷积神经网络构建三维实体椎体模型

IF 0.2

Izvestiya of Saratov University Mathematics Mechanics Informatics Pub Date : 2021-08-25 DOI: 10.18500/1816-9791-2021-21-3-368-378

A. Beskrovny, L. Bessonov, Dmitriy Ivanov, V. S. Zolotov, D. Sidorenko, I. Kirillova, L. Kossovich

引用次数: 1

Analytical algorithm of energy and time quasioptimal turn of a spacecraft under arbitrary boundary conditions 任意边界条件下航天器能量和时间准最优转弯的解析算法

IF 0.2

Izvestiya of Saratov University Mathematics Mechanics Informatics Pub Date : 2021-05-25 DOI: 10.18500/1816-9791-2021-21-2-213-226

Y. Sapunkov, A. V. Molodenkov

{"title":"Analytical algorithm of energy and time quasioptimal turn of a spacecraft under arbitrary boundary conditions","authors":"Y. Sapunkov, A. V. Molodenkov","doi":"10.18500/1816-9791-2021-21-2-213-226","DOIUrl":"https://doi.org/10.18500/1816-9791-2021-21-2-213-226","url":null,"abstract":". The optimal attitude maneuver control problem without control constraints is studied in the quaternion statement for an axially symmetric spacecraft as a rigid body under arbitrary boundary conditions on angular position and angular velocity of a spacecraft. The performance criterion is given by a functional combining the time and energy used for the attitude maneuver. Using substitutions of variables, the original problem is simpliﬁed (in terms of dynamic Euler equations) to the optimal slew problem for a rigid body with a spherical mass distribution. The simpliﬁed problem contains one additional scalar diﬀerential equation. In the class of generalized conical motions, the traditional optimal slew problem is modiﬁed to obtain analytical solutions for motion equations. The solutions contain arbitrary constants and two arbitrary scalar functions (generalized conical motion parameters). The proposed approach ﬁts well with the Poinsot concept that any arbitrary angular motion of a rigid body around a ﬁxed point can be considered as some generalized conical motion of a rigid body. Moreover, for the cases of analytic solvability of the classical problem of optimal reversal spherically symmetric spacecraft, when restrictions are imposed on the edge conditions of the problem (plane Euler turn, conical motion) solutions of the classical and modiﬁed tasks are completely the same. An optimization problem is formulated and solved with respect to these functions, the second derivatives of which serve as controls in the optimization problem. The resulting analytical solution of the modiﬁed problem can be treated as an approximate (quasioptimal) solution of the traditional optimal slew problem under arbitrary boundary conditions. The quasioptimal algorithm of the optimal turn of a spacecraft is given. Numerical example showing the closeness of the solutions of the traditional and modiﬁed optimal slew problems for an axially symmetric spacecraft is given.","PeriodicalId":42789,"journal":{"name":"Izvestiya of Saratov University Mathematics Mechanics Informatics","volume":"49 1","pages":"213-226"},"PeriodicalIF":0.2,"publicationDate":"2021-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85704397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Solutions of the Loewner equation with combined driving functions 结合驱动函数的Loewner方程的解

IF 0.2

Izvestiya of Saratov University Mathematics Mechanics Informatics Pub Date : 2021-04-14 DOI: 10.18500/1816-9791-2021-21-3-317-325

D. Prokhorov, A. Zakharov, A. Zherdev

引用次数: 1

Method of Markovian summation for study the repeated flow in queueing tandem M|GI|∞ → GI|∞ M|GI|∞→GI|∞队列中重复流的马尔可夫求和方法

IF 0.2

Izvestiya of Saratov University Mathematics Mechanics Informatics Pub Date : 2021-02-24 DOI: 10.18500/1816-9791-2021-21-1-125-137

M. Shklennik, A. Moiseev

{"title":"Method of Markovian summation for study the repeated flow in queueing tandem M|GI|∞ → GI|∞","authors":"M. Shklennik, A. Moiseev","doi":"10.18500/1816-9791-2021-21-1-125-137","DOIUrl":"https://doi.org/10.18500/1816-9791-2021-21-1-125-137","url":null,"abstract":"The paper presents a mathematical model of queueing tandem M|GI|∞ → GI|∞ with feedback. The service times at the first stage are independent and identically distributed (i.i.d.) with an arbitrary distribution function B1(x). Service times at the second stage are i.i.d. with an arbitrary distribution function B2(x). The problem is to determine the probability distribution of the number of repeated customers (r-flow) during fixed time period. To solve this problem, the Markov summation method was used, which is based on the consideration of Markov processes and the solution of the Kolmogorov equation. In the course of the solution, the so-called local r-flow was studied — the number of r-flow calls generated by one incoming customer received by the system. As a result, an expression is obtained for the characteristic probability distribution function of the number of calls in the local r-flow, which can be used to study queuing systems with a similar service discipline and non-Markov incoming flows. As a result of the study, an expression is obtained for the characteristic probability distribution function of the number of repeated calls to the system at a given time interval during non-stationary regime, which allows one to obtain the probability distribution of the number of calls in the flow under study, as well as its main probability characteristics.","PeriodicalId":42789,"journal":{"name":"Izvestiya of Saratov University Mathematics Mechanics Informatics","volume":"1 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2021-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88865919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Reconstruction formula for differential systems with a singularity 具有奇异点的微分系统的重构公式

IF 0.2

Izvestiya of Saratov University Mathematics Mechanics Informatics Pub Date : 2020-12-12 DOI: 10.18500/1816-9791-2021-21-3-282-293

M. Ignatyev

引用次数: 3

On Determination of Functional-Differential Pencils on Closed Sets from the Weyl-Type Function 由weyl型函数确定闭集上的函数微分铅笔

IF 0.2

Izvestiya of Saratov University Mathematics Mechanics Informatics Pub Date : 2020-01-01 DOI: 10.18500/1816-9791-2020-20-3-343-350

V. Yurko

引用次数: 0

Performance Analysis of Elastic Traffic with Minimum Bit Rate Guarantee Transmission in Wireless Network under Network Slicing 网络切片下无线网络最小比特率保证弹性流量的性能分析