检索结果-内蒙古大学图书馆

A new type of energy-preserving integrators for quasi-bi-Hamiltonian systems

JOURNAL OF MATHEMATICAL CHEMISTRY 2024年第7期62卷 1667-1681页

作者： Liu, Kai Fu, Ting Shi, Wei Zhou, Xuhuan Nanjing Audit Univ Dept Math Nanjing 211815 Jiangsu Peoples R China Yunnan Normal Univ Yunnan Key Lab Modern Analyt Math & Applicat Kunming 650500 Yunnan Peoples R China Natl Univ Def Technol Dept Math Changsha 410003 Hunan Peoples R China Nanjing Tech Univ Coll Math Sci Nanjing 211816 Jiangsu Peoples R China Nanjing Police Univ Dept Basic Courses Nanjing 210023 Jiangsu Peoples R China

Energy-preserving algorithms, as one of the core research areas in numerical ordinary differential equations, have achieved great success by many methods such as symplectic methods and discrete gradient methods. This paper considers the numerical integration of quasi-bi-Hamiltonian systems, which, as a generalization of bi-Hamiltonian systems, can be expressed in two distinct ways: y=P1(y)del H2(y)=1 rho (y)P2(y)del H1(y). The quasi-bi-Hamiltonian systems have two Hamiltonians H1(y) and H2(y). Conventional discrete gradient methods can only preserve one Hamiltonian at a time. In this paper, based on discrete gradient and projection, new energy-preserving integrators that can preserve the two Hamiltonians simultaneously are proposed. They show better qualitative behaviours than traditional discrete gradient methods do. Numerical integrations of Henon-Heiles type systems and the Korteweg-de Vries (KdV) equation are conducted to show the effectiveness of the new integrators in comparison with traditional discrete gradient methods.

关键词： Quasi-bi-Hamiltonian systems Energy-preserving integrators The discrete gradient methods projection algorithm Henon-Heiles type systems Korteweg-de Vries equation 65L05 65L07 65L20 65P10

来源：评论

学校读者我要写书评

暂无评论

An Efficient Method for Estimating Capability Curve of Virtual Power Plant

引用

CSEE Journal of Power and Energy Systems 2022年第3期8卷 780-788页

作者： Zhenfei Tan Haiwang Zhong Xuanyuan Wang Honghai Tang Department of Electrical Engineering State Key Laboratory of Power SystemsTsinghua UniversityBeijingChina Power exchange center State Grid Jibei Electric Power Co.LtdBeijingChina Beijing Power Exchange Center BeijingChina

To incorporate the operating constraints of a virtual power plant(VPP)in transmission-level operation and market clearing,the concept of the VPP capability curve(VPP-CC)is proposed which explicitly characterizes the allowable range of active and reactive power outputs of a VPP.A two-step projection-based calculation framework is proposed to approximate the VPP-CC by the convex hull of critical points on its *** output of the proposed algorithm is concise and can be easily incorporated in the existing system operation and market *** studies based on the IEEE 33 and 123 test feeders show the computational efficiency of the proposed method outperforms existing methods by 4~7 ***,many fewer inequalities are needed to depict the VPP-CC while achieving the comparative approximation accuracy compared to sampling-based methods,which will relieve the communication and computation burden.

关键词： Aggregation model capability curve optimal power flow projection algorithm virtual power plant

来源：评论

学校读者我要写书评

暂无评论

Adaptive tracking control of the leader-following multi-agent system with uncertainties 35

Adaptive tracking control of the leader-following multi-agen...

引用

35th Chinese Control and Decision Conference (CCDC)

作者： Zhang, Xinghong Zheng, Xiuli Henan Inst Technol Sch Elect Engn & Automat Xinxiang Henan Peoples R China

ISBN: (纸本)9798350334722

The adaptive tracking control problem of the multi-agent system is considered. The dynamics of each agent is of unknown parameter and can only receive different intensities of information from its different neighbors. To identify parameters, the improved projection algorithm is adopted, and based on each parameter estimate update law, the decentralized adaptive controllers are designed. Finally, a numerical example is provided to illustrate that each parameter estimate error is bounded and each agent tracks the desired reference trajectory.

关键词： adaptive tracking multi-agent system uncertainties projection algorithm

来源：评论

学校读者我要写书评

暂无评论

Complete Subhedge projection for Stepwise Hedge Automata

引用

algorithmS 2024年第8期17卷 339页

作者： Al Serhali, Antonio Niehren, Joachim Univ Lille Inria Ctr Lille France

We demonstrate how to evaluate stepwise hedge automata (Shas) with subhedge projection while completely projecting irrelevant subhedges. Since this requires passing finite state information top-down, we introduce the notion of downward stepwise hedge automata. We use them to define in-memory and streaming evaluators with complete subhedge projection for Shas. We then tune the evaluators so that they can decide on membership at the earliest time point. We apply our algorithms to the problem of answering regular XPath queries on Xml streams. Our experiments show that complete subhedge projection of Shas can indeed speed up earliest query answering on Xml streams so that it becomes competitive with the best existing streaming tools for XPath queries.

关键词： automata projection algorithm streaming algorithm Xml

来源：评论

学校读者我要写书评

暂无评论

A modified Solodov-Svaiter method for solving nonmonotone variational inequality problems

引用

NUMERICAL algorithmS 2022年第4期90卷 1715-1734页

作者： Bui Van Dinh Hy Duc Manh Tran Thi Huyen Thanh Le Quy Don Tech Univ Fac Informat Technol Dept Math Hanoi Vietnam VAST Inst Math Dept Optimizat & Control Theory Hanoi Vietnam

In a very interesting paper (SIAM J. Control Optim. 37(3): 765-776, 1999), Solodov and Svaiter introduced an effective projection algorithm with linesearch for finding a solution of a variational inequality problem (VIP) in Euclidean space. They showed that the iterative sequence generated by their algorithm converges to a solution of (VIP) under the main assumption that the cost mapping is pseudomonotone and continuous. In this paper, we propose to modify this algorithm for solving variational inequality problems in which the cost mapping is not required to be satisfied any pseudomonotonicity. Moreover, we do not use the embedded projection methods as in methods used in literature and the linesearch procedure is not necessary when the cost mapping is Lipschitz. Several numerical examples are also provided to illustrate the efficient of the proposed algorithms.

关键词： Non-monotonicity Variational inequalities projection algorithm Armijo linesearch

来源：评论

学校读者我要写书评

暂无评论

Non-separable multidimensional multiresolution wavelets: A Douglas-Rachford approach

引用

APPLIED AND COMPUTATIONAL HARMONIC ANALYSIS 2024年 73卷

作者： Franklin, David Hogan, Jeffrey A. Tam, Matthew K. Univ Newcastle Sch Math & Phys Sci Univ Dr Callaghan NSW 2308 Australia Univ Melbourne Sch Math & Stat Parkville Vic 3010 Australia

After re-casting the wavelet construction problem as a feasibility problem with constraints arising from the requirements of compact support, smoothness and orthogonality, the Douglas-Rachford algorithm is employed in the search for multi-dimensional, non-separable, compactly supported, smooth, orthogonal, multiresolution wavelets in the case of translations along the integer lattice and isotropic dyadic dilations. An algorithm for the numerical construction of such wavelets is described. By applying the algorithm, new one-dimensional wavelets are produced as well as genuinely non-separable two-dimensional wavelets.

关键词： Wavelets Multiresolution analysis Optimisation Douglas-Rachford algorithm projection algorithm Feasibility problem

来源：评论

学校读者我要写书评

暂无评论

Model⁃Free Predictive Control for a Kind of High Order Nonlinear Systems

引用

Journal of Harbin Institute of Technology(New Series) 2022年第2期29卷 62-69页

作者： Ye Tian Baili Su School of Engineering College Qufu Normal UniversityRizhao 276826ShandongChina

For a type of high⁃order discrete⁃time nonlinear systems(HDNS)whose system models are undefined,a model⁃free predictive control(MFPC)algorithm is proposed in this *** first,an estimation model is given by the improved projection algorithm to approach the controlled nonlinear ***,on the basis of the estimation model,a predictive controller is designed by solving the finite time domain rolling optimization quadratic function,and the controller’s explicit analytic solution is also ***,the closed⁃loop system's stability can be ***,the results of simulation reveal that the presented control strategy has a faster convergence speed as well as more stable dynamic property compared with the model⁃free sliding mode control(MFSC).

关键词： nonlinear system compact dynamic linearization(CDL) model predictive control(MPC) model-free control(MFC) projection algorithm

来源：评论

学校读者我要写书评

暂无评论

Sparsity-Exploiting Distributed projections onto a Simplex

引用

INFORMS JOURNAL ON COMPUTING 2024年第3期36卷 820-835页

作者： Dai, Yongzheng Chen, Chen Ohio State Univ Integrated Syst Engn Columbus OH 43210 USA

Projecting a vector onto a simplex is a well-studied problem that arises in a wide range of optimization problems. Numerous algorithms have been proposed for determining the projection;however, the primary focus of the literature is on serial algorithms. We present a parallel method that decomposes the input vector and distributes it across multiple processors for local projection. Our method is especially effective when the resulting projection is highly sparse, which is the case, for instance, in large-scale problems with independent and identically distributed (i.i.d.) entries. Moreover, the method can be adapted to parallelize a broad range of serial algorithms from the literature. We fill in theoretical gaps in serial algorithm analysis and develop similar results for our parallel analogues. Numerical experiments conducted on a wide range of large-scale instances, both real world and simulated, demonstrate the practical effectiveness of the method.

关键词： simplex parallel algorithm projection algorithm

来源：评论

学校读者我要写书评

暂无评论

Distributed Resource Allocation Over Directed Graphs via Continuous-Time algorithms

引用

IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS 2021年第2期51卷 1097-1106页

作者： Zhu, Yanan Ren, Wei Yu, Wenwu Wen, Guanghui Southeast Univ Sch Math Jiangsu Prov Key Lab Networked Collect Intelligen Nanjing 210096 Peoples R China Univ Calif Riverside Dept Elect & Comp Engn Riverside CA 95251 USA RMIT Univ Sch Engn Melbourne Vic 3000 Australia

This paper investigates the resource allocation problem for a group of agents communicating over a strongly connected directed graph, where the total objective function of the problem is composted of the sum of the local objective functions incurred by the agents. With local convex sets, we first design a continuous-time projection algorithm over a strongly connected and weight-balanced directed graph. Our convergence analysis indicates that when the local objective functions are strongly convex, the output state of the projection algorithm could asymptotically converge to the optimal solution of the resource allocation problem. In particular, when the projection operation is not involved, we show the exponential convergence at the equilibrium point of the algorithm. Second, we propose an adaptive continuous-time gradient algorithm over a strongly connected and weight-unbalanced directed graph for the reduced case without local convex sets. In this case, we prove that the adaptive algorithm converges exponentially to the optimal solution of the considered problem, where the local objective functions and their gradients satisfy strong convexity and Lipachitz conditions, respectively. Numerical simulations illustrate the performance of our algorithms.

关键词： Adaptive algorithm directed graphs projection algorithm resource allocation

来源：评论

学校读者我要写书评

暂无评论

A new transit assignment model based on line and node strategies

引用

TRANSPORTATION RESEARCH PART B-METHODOLOGICAL 2021年 150卷 121-142页

作者： Ren, Hualing Song, Yingjie Long, Jiancheng Si, Bingfeng Beijing Jiaotong Univ Sch Traff & Transportat Beijing 100044 Peoples R China Hefei Univ Technol Sch Automot & Transportat Engn Hefei 230009 Peoples R China

Passengers traveling on transit networks involve two kinds of decision-making strategies: deciding which lines are attractive at an origin or transfer node (denoted line strategy, LS), or deciding which node to transfer at when riding a line (denoted node strategy, NS). Combining these two strategies, this paper proposes a novel variational inequality formulation for the user equilibrium passenger assignment problem. The inclusion of the NS eliminates the need for passenger assignment on a large augmented graph, reducing the modeling complexity and making it easier to track all passengers' travel routes. Moreover, constraints on the maximal number of transfers-which are crucial in practical decision-making on transit networks-are explicitly included, further drastically reducing the set of passengers' feasible strategies. Furthermore, some extant strategy-based transit assignment models are shown to be a special case of the proposed model when the transfer constraint is removed. Finally, the properties of the proposed model are illustrated on a small network, and the model and algorithm exhibit huge advantages on the chosen transit subnetwork of Beijing.

关键词： Transit assignment Line and node strategy Transfer constraint Variational inequality problem projection algorithm

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：