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On fuzzy paratopological group and decision making during robot crash 机器人碰撞过程中的模糊类群与决策
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230205
A. Muneesh Kumar, P. Gnanachandra, S. Acharjee
In this article, we introduce fuzzy paratopological group, fuzzy semitopological group and fuzzy quasitopological group with illustrative examples and properties. These new notions belong to fuzzy topological group. Here, we prove that each fuzzy regular paratopological group is completely regular by using fuzzy uniformities. Moreover, we prove some results related to fuzzy semitopological group and fuzzy quasitopological group. In addition, we provide an application in the area of decision making during robot crash by using our above stated notions and nano topology.
本文介绍了模糊准拓扑群、模糊半拓扑群和模糊准拓扑群,并给出了具体的例子和性质。这些新概念属于模糊拓扑群。本文利用模糊均匀性证明了每一个模糊正则准拓扑群是完全正则的。此外,我们还证明了关于模糊半拓扑群和模糊拟拓扑群的一些结果。此外,我们还利用上述概念和纳米拓扑在机器人碰撞决策领域提供了一个应用。
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引用次数: 0
On one correctness problem for minimax 关于极大极小的一个正确性问题
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230206
M. S. Nikol’skii
In game theory and operations research theory, a minimax often appears for a function $f(x,y)$ that depends on two vector variables $x$, $y$. Many works have been devoted to the study of the properties of minimax (or maximin). A minimax can be interpreted as the smallest guaranteed result for the minimizing player (the minimizing operator). In the study of minimax problems, various correctness issues are of some interest. This paper is devoted to one of these issues. In it, vectors $x$, $y$ belong to compacts $P$, $Q$ of corresponding Euclidean spaces $R^k$, $R^l$, and function $f(x,y)$ is continuous on product of spaces $R^ktimes R^l$. The paper considers the dependence of minimax on small changes of compacts $P$, $Q$ in the Hausdorff metric. The continuity of the dependence of minimax on small variations of compacts $P$, $Q$ is proved.
在博弈论和运筹学理论中,函数f(x,y)$通常出现极大极小值,该函数依赖于两个向量变量$x$, $y$。对于极大极小(或极大极小)性质的研究已经有许多著作。minimax可以解释为最小化参与者(最小化操作符)的最小保证结果。在极大极小问题的研究中,各种正确性问题引起了人们的兴趣。本文专门讨论其中一个问题。其中,向量$x$, $y$属于对应欧几里德空间$R^k$, $R^l$的紧集$P$, $Q$,函数$f(x,y)$在空间$R^k乘以R^l$的积上连续。本文研究了Hausdorff度量中极大极小值对紧集$P$, $Q$变化的依赖关系。证明了极大极小值对紧集$P$, $Q$的依赖性的连续性。
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引用次数: 0
Hitting functions for mixed partitions 混合分区的命中函数
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230201
A. Dzhalilov, M. Khomidov
Let $T_{rho}$ be an irrational rotation on a unit circle $S^{1}simeq [0,1)$. Consider the sequence ${mathcal{P}_{n}}$ of increasing partitions on $S^{1}$. Define the hitting times $N_{n}(mathcal{P}_n;x,y):= inf{jgeq 1mid T^{j}_{rho}(y)in P_{n}(x)}$, where $P_{n}(x)$ is an element of $mathcal{P}_{n}$ containing $x$. D. Kim and B. Seo in [9] proved that the rescaled hitting times $K_n(mathcal{Q}_n;x,y):= frac{log N_n(mathcal{Q}_n;x,y)}{n}$ a.e. (with respect to the Lebesgue measure) converge to $log2$, where the sequence of partitions ${mathcal{Q}_n}$ is associated with chaotic map $f_{2}(x):=2x bmod 1$. The map $f_{2}(x)$ has positive entropy $log2$. A natural question is what if the sequence of partitions ${mathcal{P}_n}$ is associated with a map with zero entropy. In present work we study the behavior of $K_n(tau_n;x,y)$ with the sequence of mixed partitions ${tau_{n}}$ such that $ mathcal{P}_{n}cap [0,frac{1}{2}]$ is associated with map $f_{2}$ and $mathcal{D}_{n}cap [frac{1}{2},1]$ is associated with irrational rotation $T_{rho}$. It is proved that $K_n(tau_n;x,y)$ a.e. converges to a piecewise constant function with two values. Also, it is shown that there are some irrational rotations that exhibit different behavior.
设$T_{rho}$为单位圆$S^{1}simeq [0,1)$上的不合理旋转。考虑在$S^{1}$上增加分区的顺序${mathcal{P}_{n}}$。定义命中次数$N_{n}(mathcal{P}_n;x,y):= inf{jgeq 1mid T^{j}_{rho}(y)in P_{n}(x)}$,其中$P_{n}(x)$是包含$x$的$mathcal{P}_{n}$的一个元素。D. Kim和B. Seo在[9]中证明了重标命中次数$K_n(mathcal{Q}_n;x,y):= frac{log N_n(mathcal{Q}_n;x,y)}{n}$ a.e.(相对于Lebesgue测度)收敛于$log2$,其中分区序列${mathcal{Q}_n}$与混沌映射$f_{2}(x):=2x bmod 1$相关联。地图$f_{2}(x)$有正熵$log2$。一个自然的问题是,如果分区序列${mathcal{P}_n}$与零熵的映射相关联会怎么样?在目前的工作中,我们研究了$K_n(tau_n;x,y)$与混合分区序列${tau_{n}}$的行为,使得$ mathcal{P}_{n}cap [0,frac{1}{2}]$与映射$f_{2}$相关联,$mathcal{D}_{n}cap [frac{1}{2},1]$与不合理旋转$T_{rho}$相关联。证明了$K_n(tau_n;x,y)$ a.e.收敛于两个值的分段常数函数。此外,还发现存在一些不合理的旋转,这些旋转表现出不同的行为。
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引用次数: 0
A new hybrid conjugate gradient algorithm for unconstrained optimization 一种新的无约束优化混合共轭梯度算法
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230211
I. Hafaidia, H. Guebbai, M. Al-Baali, M. Ghiat
It is well known that conjugate gradient methods are useful for solving large-scale unconstrained nonlinear optimization problems. In this paper, we consider combining the best features of two conjugate gradient methods. In particular, we give a new conjugate gradient method, based on the hybridization of the useful DY (Dai-Yuan), and HZ (Hager-Zhang) methods. The hybrid parameters are chosen such that the proposed method satisfies the conjugacy and sufficient descent conditions. It is shown that the new method maintains the global convergence property of the above two methods. The numerical results are described for a set of standard test problems. It is shown that the performance of the proposed method is better than that of the DY and HZ methods in most cases.
众所周知,共轭梯度法是求解大规模无约束非线性优化问题的有效方法。本文考虑结合两种共轭梯度方法的最佳特征。特别地,我们在DY (Dai-Yuan)和HZ (Hager-Zhang)方法杂交的基础上,提出了一种新的共轭梯度方法。混合参数的选择使所提方法满足共轭性和充分下降条件。结果表明,新方法保持了上述两种方法的全局收敛性。本文描述了一组标准测试问题的数值结果。结果表明,在大多数情况下,该方法的性能优于DY和HZ方法。
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引用次数: 0
Two-time capture of coordinated evaders in a simple pursuit problem 简单追捕问题中协调逃兵的两次捕获
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230207
N. Petrov
In a finite-dimensional Euclidean space, the problem of pursuit of two evaders by a group of pursuers described by a system of the form$$dot z_{ij} = u_i - v,quad u_i,v in V, $$is considered. It is assumed that all evaders use the same control. The pursuers use counterstrategies based on information about the initial positions and control history of the evaders. The set of admissible controls $V$ is a unit ball centered at zero, target sets are the origin of coordinates. The goal of the pursuers' group is to capture at least one evader by two pursuers. In terms of initial positions and game parameters a sufficient condition for the capture is obtained. In the study, the method of resolving functions is used as a basic one, which allows obtaining sufficient conditions for the solvability of the approach problem in some guaranteed time.
在有限维欧几里得空间中,考虑了由$$dot z_{ij} = u_i - v,quad u_i,v in V, $$形式的系统描述的一组追赶者对两个逃避者的追赶问题。假设所有逃避者使用相同的控制。追捕者根据关于逃避者的初始位置和控制历史的信息使用对抗策略。容许控制的集合$V$是一个以0为中心的单位球,目标集合是坐标的原点。追捕者组的目标是用两名追捕者捕获至少一名逃跑者。在初始位置和博弈参数方面,得到了捕获的充分条件。在本研究中,采用函数解析法作为基本方法,可以在一定保证时间内得到逼近问题可解的充分条件。
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引用次数: 0
Stability and local bifurcations of single-mode equilibrium states of the Ginzburg-Landau variational equation Ginzburg-Landau变分方程单模平衡态的稳定性和局部分岔
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230204
D. A. Kulikov
One of the versions of the generalized variational Ginzburg-Landau equation is considered, supplemented by periodic boundary conditions. For such a boundary value problem, the question of existence, stability, and local bifurcations of single-mode equilibrium states is studied. It is shown that in the case of a nearly critical threefold zero eigenvalue, in the problem of stability of single-mode spatially inhomogeneous equilibrium states, subcritical bifurcations of two-dimensional invariant tori filled with spatially inhomogeneous equilibrium states are realized.The analysis of the stated problem is based on such methods of the theory of infinite-dimensional dynamical systems as the theory of invariant manifolds and the apparatus of normal forms. Asymptotic formulas are obtained for the solutions that form invariant tori.
考虑广义变分金兹堡-朗道方程的一种形式,并辅以周期边界条件。对于这种边值问题,研究了单模平衡态的存在性、稳定性和局部分岔问题。结果表明,在单模空间非齐次平衡态稳定性问题中,在近临界三倍零特征值的情况下,二维不变环面中充满空间非齐次平衡态的次临界分岔是可以实现的。所述问题的分析是基于无限维动力系统理论的方法,如不变流形理论和正规形式装置。得到了构成不变环面解的渐近公式。
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引用次数: 0
Numerical solution of nonstationary problem for convection of binary mixture in horizontal layer 水平层二元混合物对流非平稳问题的数值解
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230212
I. Stepanova, V. Zalizniak
Nonstationary motion of a liquid binary mixture in a narrow long horizontal channel with rigid walls heated according to a certain law is considered. The possibility of applying the Ostroumov-Birikh solution to the description of the flow under study is used. It reduces the problem to solving a mixed boundary value problem for a system of parabolic equations. A feature of the problem is an additional integral condition on the fluid flow rate. It allows finding the pressure gradient together with the functions of velocity, temperature, and concentration. Applying the constructed numerical procedure, the analysis of the obtained characteristics of motion is carried out using water-ethanol solution as a mixture. The possibilities of stabilizing the unsteady flow and controlling the motion by means of a periodically changing thermal load on the channel wall are shown.
考虑了液体二元混合物在具有刚性壁面按一定规律加热的狭长水平通道中的非定常运动。利用Ostroumov-Birikh解来描述所研究的流动的可能性。它将问题简化为求解抛物型方程组的混合边值问题。该问题的一个特点是流体流速的附加积分条件。它可以找到压力梯度以及速度,温度和浓度的函数。应用所建立的数值程序,以水-乙醇溶液为混合物,对得到的运动特性进行了分析。指出了利用周期性变化的通道壁面热负荷来稳定非定常流场和控制通道运动的可能性。
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引用次数: 0
On one problem for a fourth-order mixed-type equation that degenerates inside and on the boundary of a domain 讨论一类四阶混合型方程在区域内和边界上退化的问题
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230209
A. Urinov, D. A. Usmonov
In the article, a nonlocal boundary value problem has been investigated for a fourth-order mixed-type equation degenerating inside and on the boundary of a domain. Applying the method of separation of variables to the problem under study, the spectral problem for an ordinary differential equation is obtained. The Green function of the last problem is constructed, with the help of which it is equivalently reduced to the Fredholm integral equation of the second kind with a symmetric kernel, which implies the existence of eigenvalues and the system of eigenfunctions for the spectral problem. The theorem of expansion of a given function into a uniformly convergent series with respect to the system of eigenfunctions is proved. Using the found integral equation and Mercer's theorem, a uniform convergence of some bilinear series depending on the found eigenfunctions is proved. The order of the Fourier coefficients is established. The solution of the problem under study is written as the sum of the Fourier series with respect to the system of eigenfunctions of the spectral problem. An estimate for the problem's solution is obtained, from which its continuous dependence on the given functions follows.
研究了一类在区域边界内外退化的四阶混合型方程的非局部边值问题。将分离变量的方法应用于所研究的问题,得到了一类常微分方程的谱问题。构造了最后一个问题的Green函数,利用该函数等价地化为具有对称核的第二类Fredholm积分方程,这意味着谱问题的特征值和特征函数系的存在性。证明了给定函数在本征函数系下展开式成一致收敛级数的定理。利用所建立的积分方程和默瑟定理,证明了一类双线性级数依赖于所建立的特征函数的一致收敛性。建立了傅里叶系数的阶数。所研究问题的解被写成傅里叶级数对谱问题的特征函数系统的和。得到了问题解的估计,由此得到了问题解对给定函数的连续依赖关系。
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引用次数: 0
On multidimensional exact solutions of a nonlinear reaction-diffusion system 一类非线性反应扩散系统的多维精确解
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230203
A. A. Kosov, E. Semenov, V. V. Tirskikh
We study a multidimensional case of a nonlinear reaction-diffusion system modeled by a system of two parabolic equations with power nonlinearities. Such systems can be used to simulate the process of propagation in space of interacting distributed formations of robots of two types. Such equations also describe the processes of nonlinear diffusion in reacting two-component continuous media. An original version of the reduction method is proposed, which reduces the construction of the dependence of the exact solution on spatial variables to the solution of the Helmholtz equation, and the dependence on time to the solution of a linear system of ordinary differential equations. A number of examples of multiparameter families of exact solutions given by elementary functions are constructed.
本文研究了一类非线性反应扩散系统的多维情形,该系统由两个具有幂非线性的抛物方程组成。这种系统可以用来模拟两种类型的机器人相互作用的分布式编队在空间中的传播过程。这些方程还描述了双组分连续介质反应中的非线性扩散过程。提出了一种原始的约简方法,将精确解对空间变量的依赖简化为亥姆霍兹方程的解,将精确解对时间的依赖简化为线性常微分方程组的解。构造了由初等函数给出的精确解的多参数族的一些例子。
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引用次数: 0
Estimation of the solution of asymptotically observable linear completely regular differential-algebraic systems with delay 渐近可观察时滞线性完全正则微分-代数系统解的估计
IF 0.5 Q3 Mathematics Pub Date : 2023-06-01 DOI: 10.35634/vm230210
V. E. Khartovskii
In the article, a problem of solution estimation for linear autonomous completely regular differential-algebraic systems with many commensurate delays is investigated. The class of completely regular differential-algebraic systems with delay under study includes the classes of linear systems of delayed and neutral types; in addition, the analysis of continuous-discrete systems is reduced to completely regular systems.For linear autonomous completely regular differential-algebraic systems with many commensurate delays, the property of asymptotic observability is determined, which are characterized by the fact that all solutions generating the same output signal are indistinguishable in the future. Conditions for asymptotic observability expressed in terms of the parameters of the original system are formulated and proved. For asymptotically observable systems, a solution estimation procedure is proposed, the implementation of which consists of the following steps. First, using the observed output, a linear autonomous non-homogeneous asymptotically observable retarded type system with a non-homogeneous part depending on the output is put in correspondence with the original system. The solution of the new system uniquely determines the solution of the original system. Then a transformation is constructed that reduces the matrices of the retarded type system to a certain form. After that, with the help of a finite chain of observers, the solution is evaluated. The results of the presented study are applicable to systems that do not have the property of final observability, which makes it possible to significantly reduce the requirements for observing organs when modeling the corresponding objects of the real world.
研究了一类具有多相称时滞的线性自治完全正则微分-代数系统的解估计问题。所研究的一类具有时滞的完全正则微分代数系统包括时滞型和中立型线性系统;此外,将连续离散系统的分析简化为完全正则系统。对于具有许多等时滞的线性自治完全正则微分-代数系统,确定了其渐近可观察性的性质,其特征是产生相同输出信号的所有解在未来都是不可区分的。给出了用原系统参数表示渐近可观察性的条件,并给出了证明。对于渐近可观察系统,提出了一种解估计方法,其实现步骤如下:首先,利用观察到的输出,将具有非齐次部分依赖于输出的线性自治渐近可观察延迟型系统与原系统对应。新系统的解唯一地决定了原系统的解。然后构造了一个变换,将弱智型系统的矩阵化简为一定的形式。然后,借助有限的观察者链,对解进行求值。本文的研究结果适用于不具有最终可观测性的系统,这使得在对现实世界的相应物体建模时显著降低对观察器官的要求成为可能。
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引用次数: 0
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Vestnik Udmurtskogo Universiteta-Matematika Mekhanika Kompyuternye Nauki
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