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OPTIMAL APPROXIMATE SOLUTION OF THE MATRIX EQUATION AXB = C OVER SYMMETRIC MATRICES

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Journal of Computational Mathematics 2007年第5期25卷 543-552页

作者： Anping Liao yuan lei College of Mathematics and Econometrics Hunan University Changsha 410082 China

Let SE denote the least-squares symmetric solution set of the matrix equation A×B = C, where A, B and C are given matrices of suitable size. To find the optimal approximate solution in the set SE to a given matrix, we give a new feasible method based on the projection theorem, the generalized SVD and the canonical correction decomposition.

关键词： Least-squares solution Optimal approximate solution Generalized singular value decomposition Canonical correlation decomposition.

A POSTERIORI ERROR ESTIMATE OF OPTIMAL CONTROL PROBLEM OF PDE WITH INTEGRAL CONSTRAINT FOR STATE

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Journal of Computational Mathematics 2009年第4期27卷 525-542页

作者： lei yuan Danping Yang Department of Mathematics Shandong University Jinan 250100 China Department of Mathematics East China Normal University Shanghai 200241 China

In this paper, we study adaptive finite element discretization schemes for an optimal control problem governed by elliptic PDE with an integral constraint for the state. We derive the equivalent a posteriori error estimator for the finite element approximation, which particularly suits adaptive multi-meshes to capture different singularities of the control and the state. Numerical examples are presented to demonstrate the efficiency of a posteriori error estimator and to confirm the theoretical results.

关键词： State-constrained optimal control problem Adaptive finite element method,A posteriori error estimate.

Discontinuity-preserving optical flow algorithm

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Journal of Systems Engineering and Electronics 2007年第2期18卷 347-354页

作者： yuan lei Li Jinzong Li Dongdong Harbin Inst. of Technology Harbin 150001 P.R.China

A modification of Horn and Schunk＇s approach is investigated, which leads to a better preservation of flow discontinuities. It improves Horn-Schunk model in three aspects：（1） It replaces the smooth weight coefficient in the energy equation by the variable weight coefficient. （2） It adopts a novel method to compute the mean velocity. The novel method also reflects the effect of the intensity difference on the image velocity diffusion. （3） It introduces a more efficient iterative method than the Gauss-Seidel method to solve the associated Euler-Lagrange equation. The experiment results validate the better effect of the improved method on preserving discontinuities.

关键词： Optical flow Image sequences Differential methods PNSR.

STEM教育赋能教育强国建设:逻辑解构、问题剖析与发展策略

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广西师范大学学报（哲学社会科学版） 2025年第1期61卷 58-71页

作者：袁磊徐济远梁世松广西师范大学教育学部广西桂林541004 广西师范大学教育区块链与智能技术教育部重点实验室广西桂林541004

教育强国政策引领下,教育、科技、人才三者的协同发展是推动国家科创资源整合、未来产业发展、加快形成新质生产力的关键。而STEM教育是能衔接三者、充分发挥三者的协同发展作用的关键一环。分析中美STEM教育相关的政策文本,发现我国STE... 详细信息

教育强国政策引领下,教育、科技、人才三者的协同发展是推动国家科创资源整合、未来产业发展、加快形成新质生产力的关键。而STEM教育是能衔接三者、充分发挥三者的协同发展作用的关键一环。分析中美STEM教育相关的政策文本,发现我国STEM教育发展存在的潜在问题有三:价值错位、功能受限、生态缺失。未来要充分发挥STEM教育对教育强国建设的赋能作用,应采取三大发展策略:明确STEM教育价值定位,构建STEM教育实践指南和建设STEM教育领域融合生态。唯有多管齐下、系统推进,我国STEM教育才能真正突破发展瓶颈,焕发勃勃生机,为培养新质人才、服务国家发展战略贡献应有力量,从而推动教育强国建设迈向新的高度。

关键词： STEM教育教育强国新质人才新质生产力中国式教育现代化

Unconventional Hamilton-type variational principles for electromagnetic elastodynamics

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Science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 119-128页

作者： LUO En ZHU Huijian yuan lei Department of Applied Mechanics and Engineering Sun Yat-sen University Guangzhou 510275 China Department of Applied Mechanics and Engineering Sun Yat-sen University Guangzhou 510275 China Department of Applied Mechanics and Engineering Sun Yat-sen University Guangzhou 510275 China

According to the basic idea of classical yin-yang complementarity and modern dual-complementarity, in a simple and unified new way proposed by Luo, the unconventional Hamilton-type variational principles for electromagnetic elastodynamics can be established systematically. This new variational principles can fully characterize the initial-boundary-value problem of this dynamics. In this paper, the expression of the generalized principle of virtual work for electromagnetic dynamics is given. Based on this equation, it is possible not only to obtain the principle of virtual work in electromagnetic dynamics, but also to derive systematically the complementary functionals for eleven-field, nine-field and six-field unconventional Hamilton-type variational principles for electromagnetic elastodynamics, and the potential energy functionals for four-field and three-field ones by the generalized Legendre transformation given in this paper. Furthermore, with this approach, the intrinsic relationship among various principles can be explained clearly.

关键词： electromagnetic elastodynamics, unconventional Hamilton-type variational principle, principle of virtual work, dual-complementarity, initial-boundary-value problem.

Communication-robust multi-agent learning by adaptable auxiliary multi-agent adversary generation

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Frontiers of Computer Science 2024年第6期18卷 186331-186331页

作者： yuan lei CHEN Feng ZHANG Zongzhang YU Yang National Key Laboratory for Novel Software Technology Nanjing University Polixir Technologies

Communication can promote coordination in cooperative Multi-Agent Reinforcement Learning (MARL). Nowadays, existing works mainly focus on improving the communication efficiency of agents, neglecting that real-world communication is much more challenging as there may exist noise or potential attackers. Thus the robustness of the communication-based policies becomes an emergent and severe issue that needs more exploration. In this paper, we posit that the ego system trained with auxiliary adversaries may handle this limitation and propose an adaptable method of Multi-Agent Auxiliary Adversaries Generation for robust Communication, dubbed MA3C, to obtain a robust communication-based policy. In specific, we introduce a novel message-attacking approach that models the learning of the auxiliary attacker as a cooperative problem under a shared goal to minimize the coordination ability of the ego system, with which every information channel may suffer from distinct message attacks. Furthermore, as naive adversarial training may impede the generalization ability of the ego system, we design an attacker population generation approach based on evolutionary learning. Finally, the ego system is paired with an attacker population and then alternatively trained against the continuously evolving attackers to improve its robustness, meaning that both the ego system and the attackers are adaptable. Extensive experiments on multiple benchmarks indicate that our proposed MA3C provides comparable or better robustness and generalization ability than other baselines.

关键词： multi-agent communication adversarial training robustness validation reinforcement learning

Hemorrhagic hepatic cysts mimicking biliary cystadenoma

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World Journal of Gastroenterology 2009年第36期15卷 4601-4603页

作者： You-lei Zhang lei yuan Feng Shen Yi Wang EasternHepatobiliary Surgery Hospital Second Military MedicalUniversity Shanghai 200438 China

The hemorrhagic simple hepatic cyst is extremely rare and can sometimes be confused with biliary cystadenoma or *** we present two cases of huge hemorrhagic simple hepatic cysts. Case 1 was a 43-year-old man with a cystic lesion measuring 13 cm×12 cm in the right hepatic lobe. Ultrasound and computed tomography showed several mural nodules on the irregularly thickened wall and high-density straps inside the *** 2 was a 60-year-old woman with a huge cyst measuring 15 cm ×14 cm in the central *** and magnetic resonance imaging showed the cystic wall was unevenly thickened and there were some flame-like prominences on the *** iconographic representations of the two cases mimicked biliary *** and left hepatectomy were performed for the two patients, *** patients recovered quickly after their operations and showed no recurrence.

关键词： Simple hepatic cyst Intracystic hemorrhage Biliary cystadenoma Diagnosis Treatment

Least-Squares Solution with the Minimum-Norm for the Matrix Equation A^TXB+B^TX^TA = D and Its Applications

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 269-280页

作者： An-ping Liao yuan lei Xi-yan Hu Coilege of Mathematics and Econometrics Hunan University Changsha 410082 China Department of Mathematics and Information Sciences Changsha University Changsha 410003 China

An efficient method based on the projection theorem, the generalized singular value decomposition and the canonical correlation decomposition is presented to find the least-squares solution with the minimum-norm for the matrix equation A^TXB＋B^TX^TA = D. Analytical solution to the matrix equation is also derived. Furthermore, we apply this result to determine the least-squares symmetric and sub-antisymmetric solution of the matrix equation C^TXC = D with minimum-norm. Finally, some numerical results are reported to support the theories established in this paper.

关键词： Matrix equation minimum-norm solution generalized singular value decomposition canonical correlation decomposition

Sliding Mode Control Approach with Integrated Disturbance Observer for PMSM Speed System

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CES Transactions on Electrical Machines and Systems 2023年第1期7卷 118-127页

作者： lei yuan Yunhao Jiang Lu Xiong Pan Wang the Hubei Collaborative Innovation Center for High-efficiency Utilization of Solar Energy Hubei University of TechnologyWuhan430068China the Department of Radar System Ordnance NCO Academy of Army Engineering University of PLAWuhan430075China

The research on high-performance vector control of permanent magnet synchronous motor(PMSM)drive system plays an extremely important role in electrical drive *** further improve the speed control performance of the system,a fast non-singular end sliding mode(FNTSM)surface function based on traditional NTSM control is *** theoretical analysis proves that the FNTSM surface function has a faster dynamic response and more finite-time *** addition,for the self-vibration problem caused by high sliding mode switching gain,an FNTSM control method with anti-disturbance capability was designed based on the linear disturbance observer(DO),*** FNTSMDO method was employed to devise the PMSM speed *** comparative simulation and experiment results with traditional PI control and NTSM control methods indicate that the FNTSMDO method could improve the dynamic performance and anti-interference of the system.

关键词： PMSM Fast nonsingular terminal sliding-mode Disturbance observer PI control