四阶正则Sturm-Liouville问题的特征值依赖性分析

0 下载量 42 浏览量 更新于2024-07-16 收藏 411KB PDF 举报
"Dependence of Eigenvalues on the Regular Fourth-Order Sturm$-$Liouville Problem" 四阶正则Sturm-Liouville问题的研究在数学分析领域占据着重要的地位,尤其是在理论物理和工程计算中有着广泛的应用。Sturm-Liouville问题是一类特殊的线性微分方程,它涉及一个二阶线性偏微分方程,通常包含有位置依赖的权重函数和边界条件。这类问题在量子力学、振动理论和数学物理中尤为常见。 在Sturm-Liouville理论中,特征值是问题的关键属性,它们决定了解的性质。这些特征值不仅与问题的结构紧密相关,还直接影响到物理系统的特性。传统的Sturm-Liouville问题通常是二阶的,但在此文中,作者探讨的是四阶的变种,这使得问题的复杂性增加,研究特征值的依赖性更具挑战性。 文章的作者索建青、师志洁和魏臻来自内蒙古大学数学科学学院,他们提出,对于四阶正则的Sturm-Liouville问题,特征值不仅对问题本身连续依赖,而且这种依赖关系是光滑的。这意味着特征值的变化率随着问题参数(如区间端点、边界条件、系数以及权函数)的变化而变化,并且可以精确地表达出来。这一点对于理解和预测系统行为具有重要意义,因为它提供了计算特征值对参数敏感性的工具。 在论文中,作者给出了特征值关于这些参数的导数表达式。这些表达式可能是微分方程的形式,允许研究人员通过数值或解析方法求解,以确定特征值的变化。这在实际应用中非常有用,例如在工程设计中优化系统参数时,或者在量子物理中计算能级时。 关键词“四阶Sturm-Liouville问题”指明了研究的对象,而“连续依赖性”和“特征值”强调了研究的核心内容,即特征值如何随着问题参数的变化而连续变化。中图分类号“O175.3”表明这是属于数学分析的一个子领域。 0引言部分提到,Sturm-Liouville理论起源于19世纪初,由Sturm和Liouville的工作奠定基础。他们的贡献对这个领域的形成和发展产生了深远影响。至今,Sturm-Liouville理论仍然是解决线性微分方程边值问题的强有力工具。 这篇论文为理解四阶Sturm-Liouville问题的特征值提供了一种新的分析方法,不仅深化了理论认识,也对实际应用提供了计算上的支持。通过研究特征值的连续性和光滑依赖性,科学家和工程师能够更准确地模拟和控制那些由这类问题描述的物理系统。
2017-06-19 上传
This accessible book provides an introduction to the analysis and design of dynamic multiagent networks. Such networks are of great interest in a wide range of areas in science and engineering, including: mobile sensor networks, distributed robotics such as formation flying and swarming, quantum networks, networked economics, biological synchronization, and social networks. Focusing on graph theoretic methods for the analysis and synthesis of dynamic multiagent networks, the book presents a powerful new formalism and set of tools for networked systems. The book's three sections look at foundations, multiagent networks, and networks as systems. The authors give an overview of important ideas from graph theory, followed by a detailed account of the agreement protocol and its various extensions, including the behavior of the protocol over undirected, directed, switching, and random networks. They cover topics such as formation control, coverage, distributed estimation, social networks, and games over networks. And they explore intriguing aspects of viewing networks as systems, by making these networks amenable to control-theoretic analysis and automatic synthesis, by monitoring their dynamic evolution, and by examining higher-order interaction models in terms of simplicial complexes and their applications. The book will interest graduate students working in systems and control, as well as in computer science and robotics. It will be a standard reference for researchers seeking a self-contained account of system-theoretic aspects of multiagent networks and their wide-ranging applications. This book has been adopted as a textbook at the following universities: University of Stuttgart, Germany Royal Institute of Technology, Sweden Georgia Tech, USA University of Washington, USA Ohio University, USA

帮我地道的翻译:The differential variational inequalities ((DVIs), for short) are useful for the study of models involving both dynamics and constraints in the form of in￾equalities. They arise in many applications: electrical circuits with ideal diodes, Coulomb friction problems for contacting bodies, economical dynamics, dynamic traffic networks. Pang and Stewart [26], [27] established the existence, unique￾ness, and Lipschitz dependence of solutions subject to boundary conditions for (DVIs) in finite dimensional spaces. Han and Pang investigated a class of dif￾ferential quasi-variational inequalities in [11], and Li, Huang and O’Regan [18] studied a class of differential mixed variational inequalities in finite dimensional Well-Posedness of Differential Mixed Quasi-Variational-Inequalities 137 spaces. Gwinner [8] obtained an equivalence result between (DVIs) and projected dynamical systems. In [9] he also proved a stability property for (DVIs) by using the monotonicity method of Browder and Minty, and Mosco set convergence. Chen and Wang [4] studied dynamic Nash equilibrium problems which have the formulation of differential mixed quasi-variational inequalities. Elastoplastic contact problems can also be incorporated into (DMQVIs) formulation because general dynamic processes in the nonsmooth unilateral contact problems are governed by quasi-variational inequalities. A numerical study for nonsmooth contact problems with Tresca friction can be found in [10], Liu, Loi and Obukhovskii [19] studied the existence and global bifurcation for periodic solutions of a class of (DVIs) by using the topological degree theory for multivalued maps and the method of guiding functions. For more details about (DVIs) we refer to [3], [30], [12], [22]–[21].

2023-05-30 上传

这一段讲的是什么:Abstract—A recent trojan attack on deep neural network (DNN) models is one insidious variant of data poisoning attacks. Trojan attacks exploit an effective backdoor created in a DNN model by leveraging the difficulty in interpretability of the learned model to misclassify any inputs signed with the attacker’s chosen trojan trigger. Since the trojan trigger is a secret guarded and exploited by the attacker, detecting such trojan inputs is a challenge, especially at run-time when models are in active operation. This work builds STRong Intentional Perturbation (STRIP) based run-time trojan attack detection system and focuses on vision system. We intentionally perturb the incoming input, for instance by superimposing various image patterns, and observe the randomness of predicted classes for perturbed inputs from a given deployed model—malicious or benign. A low entropy in predicted classes violates the input-dependence property of a benign model and implies the presence of a malicious input—a characteristic of a trojaned input. The high efficacy of our method is validated through case studies on three popular and contrasting datasets: MNIST, CIFAR10 and GTSRB. We achieve an overall false acceptance rate (FAR) of less than 1%, given a preset false rejection rate (FRR) of 1%, for different types of triggers. Using CIFAR10 and GTSRB, we have empirically achieved result of 0% for both FRR and FAR. We have also evaluated STRIP robustness against a number of trojan attack variants and adaptive attacks. Index Terms—Trojan attack, Backdoor attack

2023-07-24 上传