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Numerical simulation of time fractional Allen-Cahn equation based on Hermite neural solver 基于Hermite神经解算器的时间分数阶Allen-Cahn方程数值模拟
IF 4 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-05 DOI: 10.1016/j.amc.2024.129234
Xin Wang, Xiaoping Wang, Haitao Qi, Huanying Xu
In this paper, we introduce a high-precision Hermite neural network solver which employs Hermite interpolation technique to construct high-order explicit approximation schemes for fractional derivatives. By automatically satisfying the initial conditions, the construction process of the objective function is simplified, thereby reducing the complexity of the solution. Our neural networks are trained and fine-tuned to solve one-dimensional (1D) and two-dimensional (2D) time fractional Allen-Cahn equations with limited sampling points, yielding high-precision results. Additionally, we tackle the parameter inversion problem by accurately recovering model parameters from observed data, thereby validating the efficacy of the proposed algorithm. We compare the L2 relative error between the exact solution and the predicted solution to verify the robustness and accuracy of the algorithm. This analysis confirms the reliability of our method in capturing the fundamental dynamics of equations. Furthermore, we extend our analysis to three-dimensional (3D) cases, which is covered in the appendix, and provide a thorough evaluation of the performance of our method. This paper also conducts comprehensive analysis of the network structure. Numerical experiments indicate that the number of layers, the number of neurons in each layer, and the choice of learning rate play a crucial role in the performance of our solver.
本文介绍了一种高精度的Hermite神经网络求解器,它利用Hermite插值技术构造分数阶导数的高阶显式逼近格式。通过自动满足初始条件,简化了目标函数的构造过程,从而降低了求解的复杂性。我们的神经网络经过训练和微调,可以在有限的采样点下解决一维(1D)和二维(2D)时间分数艾伦-卡恩方程,从而产生高精度的结果。此外,我们通过从观测数据中准确恢复模型参数来解决参数反演问题,从而验证了所提出算法的有效性。我们比较了精确解和预测解之间的L2相对误差,以验证算法的鲁棒性和准确性。这一分析证实了我们的方法在捕捉方程基本动力学方面的可靠性。此外,我们将分析扩展到附录中涵盖的三维(3D)案例,并对我们的方法的性能进行了全面的评估。本文还对网络结构进行了综合分析。数值实验表明,层数、每层神经元数和学习率的选择对求解器的性能起着至关重要的作用。
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引用次数: 0
Mutual and total mutual visibility in hypercube-like graphs 超立方体图中的互可见性和全互可见性
IF 4 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-03 DOI: 10.1016/j.amc.2024.129216
Serafino Cicerone, Alessia Di Fonso, Gabriele Di Stefano, Alfredo Navarra, Francesco Piselli
Let G be a graph and XV(G). Then, vertices x and y of G are X-visible if there exists a shortest x,y-path where no internal vertices belong to X. The set X is a mutual-visibility set of G if every two vertices of X are X-visible, while X is a total mutual-visibility set if any two vertices from V(G) are X-visible. The cardinality of a largest mutual-visibility set (resp. total mutual-visibility set) is the mutual-visibility number (resp. total mutual-visibility number) μ(G) (resp. μt(G)) of G. It is known that computing μ(G) is an NP-complete problem, as well as μt(G). In this paper, we study the (total) mutual-visibility in hypercube-like networks (namely, hypercubes, Fibonacci cubes, cube-connected cycles, and butterflies). Concerning computing μ(G), we provide approximation algorithms for hypercubes, Fibonacci cubes and cube-connected cycles, while we give an exact formula for butterflies. Concerning computing μt(G) (in the literature, already studied in hypercubes), whereas we obtain exact formulae for both cube-connected cycles and butterflies.
设G为图,X⊥V(G)。那么,如果存在一条最短的x,y路径且不存在内部顶点属于x,则G的顶点x和y是x可见的。如果x的每两个顶点都是x可见,则集合x是G的互可见集,如果V(G)中的任意两个顶点都是x可见集,则x是总互可见集。最大互可见性集的基数。总互可见性集)是互可见性数(例如:总互可视性数μ(G)μt(G))是一个np完全问题,μt(G)也是一个np完全问题。在本文中,我们研究了超立方体网络(即超立方体、斐波那契立方体、立方体连接环和蝴蝶)中的(总)互可见性。关于μ(G)的计算,我们给出了超立方体、斐波那契立方体和立方连通循环的近似算法,同时给出了蝴蝶的精确计算公式。关于μt(G)的计算(在文献中,已经在超立方体中研究过),而我们得到了立方体连接循环和蝴蝶的精确公式。
{"title":"Mutual and total mutual visibility in hypercube-like graphs","authors":"Serafino Cicerone, Alessia Di Fonso, Gabriele Di Stefano, Alfredo Navarra, Francesco Piselli","doi":"10.1016/j.amc.2024.129216","DOIUrl":"https://doi.org/10.1016/j.amc.2024.129216","url":null,"abstract":"Let <ce:italic>G</ce:italic> be a graph and <mml:math altimg=\"si3.svg\"><mml:mi>X</mml:mi><mml:mo>⊆</mml:mo><mml:mi>V</mml:mi><mml:mo stretchy=\"false\">(</mml:mo><mml:mi>G</mml:mi><mml:mo stretchy=\"false\">)</mml:mo></mml:math>. Then, vertices <ce:italic>x</ce:italic> and <ce:italic>y</ce:italic> of <ce:italic>G</ce:italic> are <ce:italic>X</ce:italic>-visible if there exists a shortest <mml:math altimg=\"si4.svg\"><mml:mi>x</mml:mi><mml:mo>,</mml:mo><mml:mi>y</mml:mi></mml:math>-path where no internal vertices belong to <ce:italic>X</ce:italic>. The set <ce:italic>X</ce:italic> is a mutual-visibility set of <ce:italic>G</ce:italic> if every two vertices of <ce:italic>X</ce:italic> are <ce:italic>X</ce:italic>-visible, while <ce:italic>X</ce:italic> is a total mutual-visibility set if any two vertices from <mml:math altimg=\"si5.svg\"><mml:mi>V</mml:mi><mml:mo stretchy=\"false\">(</mml:mo><mml:mi>G</mml:mi><mml:mo stretchy=\"false\">)</mml:mo></mml:math> are <ce:italic>X</ce:italic>-visible. The cardinality of a largest mutual-visibility set (resp. total mutual-visibility set) is the mutual-visibility number (resp. total mutual-visibility number) <mml:math altimg=\"si6.svg\"><mml:mi>μ</mml:mi><mml:mo stretchy=\"false\">(</mml:mo><mml:mi>G</mml:mi><mml:mo stretchy=\"false\">)</mml:mo></mml:math> (resp. <mml:math altimg=\"si7.svg\"><mml:msub><mml:mrow><mml:mi>μ</mml:mi></mml:mrow><mml:mrow><mml:mi>t</mml:mi></mml:mrow></mml:msub><mml:mo stretchy=\"false\">(</mml:mo><mml:mi>G</mml:mi><mml:mo stretchy=\"false\">)</mml:mo></mml:math>) of <ce:italic>G</ce:italic>. It is known that computing <mml:math altimg=\"si6.svg\"><mml:mi>μ</mml:mi><mml:mo stretchy=\"false\">(</mml:mo><mml:mi>G</mml:mi><mml:mo stretchy=\"false\">)</mml:mo></mml:math> is an NP-complete problem, as well as <mml:math altimg=\"si7.svg\"><mml:msub><mml:mrow><mml:mi>μ</mml:mi></mml:mrow><mml:mrow><mml:mi>t</mml:mi></mml:mrow></mml:msub><mml:mo stretchy=\"false\">(</mml:mo><mml:mi>G</mml:mi><mml:mo stretchy=\"false\">)</mml:mo></mml:math>. In this paper, we study the (total) mutual-visibility in hypercube-like networks (namely, hypercubes, Fibonacci cubes, cube-connected cycles, and butterflies). Concerning computing <mml:math altimg=\"si6.svg\"><mml:mi>μ</mml:mi><mml:mo stretchy=\"false\">(</mml:mo><mml:mi>G</mml:mi><mml:mo stretchy=\"false\">)</mml:mo></mml:math>, we provide approximation algorithms for hypercubes, Fibonacci cubes and cube-connected cycles, while we give an exact formula for butterflies. Concerning computing <mml:math altimg=\"si7.svg\"><mml:msub><mml:mrow><mml:mi>μ</mml:mi></mml:mrow><mml:mrow><mml:mi>t</mml:mi></mml:mrow></mml:msub><mml:mo stretchy=\"false\">(</mml:mo><mml:mi>G</mml:mi><mml:mo stretchy=\"false\">)</mml:mo></mml:math> (in the literature, already studied in hypercubes), whereas we obtain exact formulae for both cube-connected cycles and butterflies.","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"42 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142790146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Low-rank quaternion matrix completion based on approximate quaternion SVD and sparse regularizer 基于近似四元数SVD和稀疏正则化器的低秩四元数矩阵补全
IF 4 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-03 DOI: 10.1016/j.amc.2024.129230
Juan Han, Liqiao Yang, Kit Ian Kou, Jifei Miao, Lizhi Liu
Matrix completion is a challenging problem in computer vision. Recently, quaternion representations of color images have achieved competitive performance in many fields. The information on the coupling between the three channels of the color image is better utilized since the color image is treated as a whole. Due to this, researcher interest in low-rank quaternion matrix completion (LRQMC) algorithms has grown significantly. In contrast to the traditional quaternion matrix completion algorithms that rely on quaternion singular value decomposition (QSVD), we propose a novel method based on quaternion Qatar Riyal decomposition (QQR). First, a novel approach (CQSVD-QQR) to computing an approximation of QSVD based on iterative QQR is put forward, which has lower computational complexity than QSVD. CQSVD-QQR can be employed to calculate the greatest r(r>0) singular values of a given quaternion matrix. Following that, we propose a novel quaternion matrix completion approach based on CQSVD-QQR which combines low-rank and sparse priors of color images. Furthermore, the convergence of the algorithm is analyzed. Our model outperforms those state-of-the-art approaches following experimental results on natural color images and color medical images.
矩阵补全是计算机视觉中的一个具有挑战性的问题。近年来,彩色图像的四元数表示在许多领域都取得了具有竞争力的表现。由于将彩色图像作为一个整体来处理,因此可以更好地利用彩色图像的三个通道之间的耦合信息。因此,研究者对低秩四元数矩阵补全(LRQMC)算法的兴趣日益浓厚。针对传统的基于四元数奇异值分解(QSVD)的四元数矩阵补全算法,提出了一种基于四元数卡塔尔里亚尔分解(QQR)的四元数矩阵补全算法。首先,提出了一种基于迭代QQR的计算QSVD近似的新方法(CQSVD-QQR),该方法的计算复杂度低于QSVD。CQSVD-QQR可用于计算给定四元数矩阵的最大r(r>0)个奇异值。在此基础上,提出了一种结合彩色图像低秩先验和稀疏先验的基于CQSVD-QQR的四元数矩阵补全方法。进一步分析了算法的收敛性。我们的模型在自然彩色图像和彩色医学图像上的实验结果优于那些最先进的方法。
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引用次数: 0
Analysis of viewpoint evolution based on WeiBo data mining 基于微博数据挖掘的视点演化分析
IF 3.5 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-02 DOI: 10.1016/j.amc.2024.129212
Sichen Tang, Aili Fang
In the era of rapid development of the Internet, in order to reflect the evolution process of users' viewpoints on network relations, a Bayesian viewpoint evolution model based on Weibo data mining is proposed by studying the relationship between the viewpoints of the author and those of the forwarders on the Sina Weibo platform. Firstly, Python crawler technology was used to crawl the comments and forwarding data under the Weibo topic “#ChatGPT father says human-level AI is coming soon”. After data preprocessing and sentiment analysis, the user relationship network diagram was drawn with Gephi software. Secondly, the viewpoint evolution model is constructed and the viewpoint update formula based on Bayes rule is used to calculate the users' viewpoint evolution within the network relations of several kinds of different publication centers. The results show that: in the communication of public opinion, the evolution direction of the opinions of the media-centered network relations tends to be more consistent, which indicates the importance of the opinion guidance of the media in the communication of information. The analysis and technology provide a certain reference for the government and the media to control and guide the network public opinion.
在互联网快速发展的时代,为了反映用户对网络关系的观点演变过程,通过研究新浪微博平台上作者观点与转发者观点之间的关系,提出了基于微博数据挖掘的贝叶斯观点演变模型。首先,使用Python爬虫技术抓取微博主题“#ChatGPT父亲说人类级别的人工智能即将到来”下的评论和转发数据。经过数据预处理和情感分析,利用Gephi软件绘制用户关系网络图。其次,构建了视点演化模型,利用基于贝叶斯规则的视点更新公式计算了几种不同出版中心网络关系内用户的视点演化;结果表明:在舆论传播中,以媒体为中心的网络关系的舆论演变方向趋于一致,这表明媒体的舆论引导在信息传播中的重要性。分析和技术为政府和媒体控制和引导网络舆论提供了一定的参考。
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引用次数: 0
Exploring threshold dynamics in a spatially heterogeneous ecosystem with memory-based diffusion and hunting cooperation on predators 基于记忆扩散和捕食合作的空间异质性生态系统阈值动态研究
IF 3.5 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-02 DOI: 10.1016/j.amc.2024.129221
Zidie Zhang, Daiyong Wu, Nishan Li
Recognizing the threshold dynamics of highly developed animals with memory is significant for the governance of species within a specific domain. To investigate how the memory threshold affects population behavior, we formulate a spatially heterogeneous predator-prey system with memory-based diffusion and hunting cooperation on predators. In homogeneous environments, the occurrence conditions of Turing bifurcation and spatially inhomogeneous Hopf bifurcations respectively induced by the memory-based diffusion coefficient and the average memory period at coexistence constant steady states are investigated. Then, in heterogeneous environments, the stability of predator-free steady state is studied by the variational characterization of the principal eigenvalue, and the explicit expression of coexistence steady states is established by the implicit function theorem. In both homogeneous and heterogeneous environments, as the average memory period is beyond the thresholds, the spatially inhomogeneous periodic solutions occur by numerical simulations. Moreover, the increase of cooperative hunting can improve the predation rate of predators, thereby leading to the emergence of periodic solutions. It is worth noting that the introduction of heterogeneous environments results in a transition in spatial patterns from predator-free steady states to spatially inhomogeneous solutions, which biologically indicates that the heterogeneous environments are more conducive to predator invasion than homogeneous ones.
认识到具有记忆的高度发达动物的阈值动态对于特定领域内物种的治理具有重要意义。为了研究记忆阈值对种群行为的影响,我们构建了一个基于记忆扩散和捕食合作的空间异质性捕食者-猎物系统。在齐次环境下,研究了基于记忆的扩散系数和共存常稳态下的平均记忆周期分别诱发图灵分岔和空间非齐次Hopf分岔的发生条件。然后,利用主特征值的变分特征研究了异质环境下无捕食者稳态的稳定性,利用隐函数定理建立了共存稳态的显式表达式。在均匀和非均匀环境下,当平均记忆周期超过阈值时,通过数值模拟都出现了空间非均匀周期解。此外,合作狩猎的增加可以提高捕食者的捕食率,从而导致周期性解决方案的出现。值得注意的是,异质环境的引入导致了空间格局从无捕食者的稳定状态向空间非均匀解决方案的转变,这在生物学上表明异质环境比均匀环境更有利于捕食者的入侵。
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引用次数: 0
Hybrid control for the prey in a spatial prey-predator model with cooperative hunting and fear effect time lag 具有合作捕猎和恐惧效应时滞的空间捕食模型中猎物的混合控制
IF 3.5 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-02 DOI: 10.1016/j.amc.2024.129217
Yu Mu , Wing-Cheong Lo , Yuanshun Tan , Zijian Liu
In the ecosystem, the chase of the predator with cooperation contributes to fear psychology in the prey, resulting in behavioral changes such as a decrease in the birth rate. We construct a spatially diffusive model with delay to investigate the combined perturbation of these factors. Initially, we establish the existence of positive solutions and examine the stability of steady-state solutions under varying conditions. The bifurcation dynamics of the positive solutions have been analyzed. Turing instability, arising from the random diffusion of the species, generates spatially irregular patterns characterized by patchy distribution of prey and predators in the spatial domain. Hopf bifurcation, resulting from the diffusive rate and delay, contributes to spatially periodic solutions where the number of species will spatially oscillate. The combined influence of diffusion and delay results in the emergence of Turing and Hopf bifurcation phenomena. In this case, the combined effect amplifies the spatially heterogeneous distribution of prey and predator. Our results reveal the heterogeneous behaviors of prey and predator under the coupled influence of cooperation hunting and fear effects. In this paper, we will also study a hybrid control scheme for controlling the generations of Turing patterns and Hopf bifurcation. Our theoretical results and numerical simulations demonstrate that the control scheme can mitigate the negative influence of combined factors and promote the species' stability.
在生态系统中,合作追逐捕食者会使猎物产生恐惧心理,从而导致出生率下降等行为变化。我们构造了一个带延迟的空间扩散模型来研究这些因素的联合摄动。首先,我们建立了正解的存在性,并检验了变条件下稳态解的稳定性。对正解的分岔动力学进行了分析。图灵不稳定性是由于物种的随机扩散而产生的,它在空间上产生了不规则的模式,其特征是猎物和捕食者在空间域中的分布是不均匀的。Hopf分岔是由扩散速率和延迟引起的,有助于得到空间周期解,其中物种数量将在空间上振荡。扩散和延迟的共同影响导致了图灵和Hopf分岔现象的出现。在这种情况下,综合效应放大了猎物和捕食者的空间异质性分布。我们的研究结果揭示了在合作捕猎和恐惧效应的双重影响下,猎物和捕食者行为的异质性。在本文中,我们还将研究一种用于控制图灵模式和Hopf分岔生成的混合控制方案。理论结果和数值模拟结果表明,该控制方案能够减轻组合因素的负面影响,提高物种的稳定性。
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引用次数: 0
Variety of mutual-visibility problems in hypercubes 超立方体中各种互可见性问题
IF 3.5 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-02 DOI: 10.1016/j.amc.2024.129218
Danilo Korže , Aleksander Vesel
Let G be a graph and MV(G). Vertices x,yM are M-visible if there exists a shortest x,y-path of G that does not pass through any vertex of M{x,y}. We say that M is a mutual-visibility set if each pair of vertices of M is M-visible, while the size of any largest mutual-visibility set of G is the mutual-visibility number of G. If some additional combinations for pairs of vertices x,y are required to be M-visible, we obtain the total (every x,yV(G) are M-visible), the outer (every xM and every yV(G)M are M-visible), and the dual (every x,yV(G)M are M-visible) mutual-visibility set of G. The cardinalities of the largest of the above defined sets are known as the total, the outer, and the dual mutual-visibility number of G, respectively.
We present results on the variety of mutual-visibility problems in hypercubes.
设G为图,M⊥V(G)。顶点x,y∈M是M可见的,如果存在G的最短路径x,y不经过M的任何顶点{x,y}。如果M的每个顶点对都是M可见的,则M是一个互可见集,而G的任何最大的互可见集的大小是G的互可见数。如果要求顶点对x,y的一些附加组合是M可见的,则我们得到total(每个x,y∈V(G)), outer(每个x∈M和每个y∈V(G)∈M)是M可见的,和G的对偶可见集(每个x,y∈V(G)∈M是M可见的)。上述定义集合中最大的集合的基数分别称为G的总可见数、外可见数和对偶可见数。我们给出了超立方体中各种互可见性问题的结果。
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引用次数: 0
A proximal bundle approach for solving the generalized variational inequalities with inexact data 求解不精确数据下广义变分不等式的近端束方法
IF 3.5 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-02 DOI: 10.1016/j.amc.2024.129087
Ming Huang , Si Qi Zhang , Yong Xiu Feng , Jin Long Yuan , Hong Han Bei
This paper introduces a proximal bundle scheme to solve generalized variational inequalities with inexact data. Under optimality conditions, the problem can be equivalently represented as seeking out the zero point of the sum of two multi-valued operators whose domains are the real Hilbert space. The two operators denoted by T and f, respectively, are the monotone operator and the subdifferential of a lower semi-continuous, non-differentiable, convex function. Our approach is based on the principles of the proximal point strategy, which involves incorporating inexact information into the subproblems and approximating them using a series of piecewise linear convex functions. Moreover, we put forward a novel stopping criterion to identify the adequacy of the current approximation. This approach serves to make the subproblems more manageable, and it has been proven that obtaining inexact information can ensure that the linearization error during the iteration process remains non-negative, thus avoiding triggering noise attenuation. Subsequently, we verify the convergence of the algorithm under relatively mild assumptions (the operator T is para-monotone and may be multi-valued). Ultimately, we present the findings of elementary numerical experiments to declare the method's efficacy.
介绍了一种求解不精确数据下广义变分不等式的近端束格式。在最优性条件下,该问题可等价地表示为求域为实数Hilbert空间的两个多值算子和的零点。用T和f分别表示的两个算子是下半连续不可微凸函数的单调算子和次微分。我们的方法基于近点策略的原则,该策略涉及将不精确信息纳入子问题,并使用一系列分段线性凸函数逼近它们。此外,我们提出了一个新的停止准则,以确定当前逼近的充分性。这种方法可以使子问题更易于管理,并且已经证明,获取不精确的信息可以确保迭代过程中的线性化误差不为负,从而避免触发噪声衰减。随后,我们在相对温和的假设下验证了算法的收敛性(算子T是拟单调的,可以是多值的)。最后,我们给出了初步的数值实验结果来证明该方法的有效性。
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引用次数: 0
Past-performance-driven strategy updating promote cooperation in the spatial prisoner's dilemma game 过去绩效驱动的策略更新促进了空间囚徒困境博弈中的合作
IF 3.5 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-02 DOI: 10.1016/j.amc.2024.129220
Shounan Lu , Yang Wang
Strategy update rules play an important role in repeated Prisoner's Dilemma games. This work proposes a modified strategy update rule based on the traditional Fermi function, in which individual past performance is taken into account in strategy update. Then, the consistency aspiration α serves as a benchmark to measure an individual's past performance, and the past performance score is dynamically adjusted during the evolution process according to the BM reinforcement learning rules. The computational results indicate that the proposed modified strategy update rules can significantly improve system cooperation t than the traditional version, and the network reciprocity effect is enhanced as the result of past performance is coupled into the strategy update rule. Moreover, different temptation to defection b exist a corresponding aspiration α result in maximizing system cooperation. Furthermore, an optimal sensitivity level β can also result in a maximizing system cooperation. As a whole, for α − β phase diagram, different a will correspond to an optimal value β that allows the system to achieve the maximum cooperation. Finally, the proposed mechanism is robust. Hopefully this can help to inspire further research on how to deal with social dilemmas.
策略更新规则在重复囚徒困境博弈中起着重要作用。本文在传统费米函数的基础上提出了一种改进的策略更新规则,该规则在策略更新中考虑了个体过去的表现。然后,以一致性期望α作为衡量个体过去绩效的基准,并在进化过程中根据BM强化学习规则动态调整过去绩效得分。计算结果表明,与传统策略更新规则相比,改进后的策略更新规则可以显著提高系统的协作性,并且由于将过去的性能耦合到策略更新规则中,网络的互惠效应得到增强。此外,存在不同的背叛诱惑b和相应的愿望α,使得系统合作最大化。此外,最优的灵敏度水平β也可以使系统合作最大化。总的来说,对于α - β相图,不同的a将对应一个最优值β,使系统达到最大的合作。最后,该机制具有鲁棒性。希望这能对如何处理社会困境的进一步研究有所启发。
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引用次数: 0
Convergence analysis of a regularized Newton method with generalized regularization terms for unconstrained convex optimization problems 无约束凸优化问题的广义正则化牛顿法的收敛性分析
IF 3.5 2区 数学 Q1 MATHEMATICS, APPLIED Pub Date : 2024-12-02 DOI: 10.1016/j.amc.2024.129219
Yuya Yamakawa, Nobuo Yamashita
This paper presents a regularized Newton method (RNM) with generalized regularization terms for unconstrained convex optimization problems. The generalized regularization includes quadratic, cubic, and elastic net regularizations as special cases. Therefore, the proposed method serves as a general framework that includes not only the classical and cubic RNMs but also a novel RNM with elastic net regularization. We show that the proposed RNM has the global O(k2) and local superlinear convergence, which are the same as those of the cubic RNM.
针对无约束凸优化问题,提出了一种具有广义正则项的正则牛顿法。广义正则化包括二次正则化、三次正则化和弹性网正则化。因此,本文提出的方法不仅是一个包含经典RNM和三次RNM的总体框架,而且是一个具有弹性网络正则化的新型RNM。我们证明了该RNM具有与三次RNM相同的全局O(k−2)和局部超线性收敛性。
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引用次数: 0
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Applied Mathematics and Computation
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