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美国能源部重大科技基础设施对我国开放服务趋势研究及启示

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中国科学院院刊 2024年第3期39卷 459-471页

作者：董璐李宜展李云龙王学昭李泽霞中国科学院文献情报中心北京100190 中国科学院大学经济与管理学院信息资源管理系北京101407 中国科学院前沿科学与教育局北京100864

重大科技基础设施(以下简称“重大设施”)是大科学时代创新的关键,是体现一个国家科技创新能力和综合国力的重要标志。为抢占科技制高点,世界主要发达国家在积极发展和优化重大设施布局的同时,大力推进重大设施开放共享以实现科技资源... 详细信息

重大科技基础设施(以下简称“重大设施”)是大科学时代创新的关键,是体现一个国家科技创新能力和综合国力的重要标志。为抢占科技制高点,世界主要发达国家在积极发展和优化重大设施布局的同时,大力推进重大设施开放共享以实现科技资源的高效配置和利用,将其科技基础条件优势转化为创新发展优势。美国能源部目前管理28个向全球科研用户开放的国家重大设施。文章通过梳理美国能源部重大设施开放共享现状,深入剖析2015—2022年我国对美国能源部重大设施的使用需求、成效和困境,以期为我国重大科技基础设施的开放共享及布局建设提供参考借鉴。

关键词：美国能源部重大科技基础设施开放服务布局建设

Solving Multivariate Polynomial Matrix Diophantine Equations with Gr?bner Basis Method

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Journal of Systems Science & Complexity 2022年第1期35卷 413-426页

作者： XIAO Fanghui lu dong WANG Dingkang College of Mathematics and Statistics Hunan Normal UniversityChangsha 410006China Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang UniversityBeijing 100191China School of Mathematical Sciences Beihang UniversityBeijing 100191China. KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

Different from previous viewpoints,multivariate polynomial matrix Diophantine equations are studied from the perspective of modules in this paper,that is,regarding the columns of matrices as elements in modules.A necessary and sufficient condition of the existence for the solution of equations is *** powerful features and theoretical foundation of Gr?bner bases for modules,the problem for determining and computing the solution of matrix Diophantine equations can be ***,the authors make use of the extension on modules for the GVW algorithm that is a signature-based Gr?bner basis algorithm as a powerful tool for the computation of Gr?bner basis for module and the representation coefficients problem directly related to the particular solution of *** a consequence,a complete algorithm for solving multivariate polynomial matrix Diophantine equations by the Gr?bner basis method is presented and has been implemented on the computer algebra system Maple.

关键词： Gr?bner basis matrix Diophantine equation module multivariate polynomial

Hybrid Q-learning for data-based optimal control of non-linear switching system

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Journal of Systems Engineering and Electronics 2022年第5期33卷 1186-1194页

作者： LI Xiaofeng dong lu SUN Changyin School of Automation Southeast UniversityNanjing 210096China School of Artificial Intelligence Anhui UniversityHefei 230601China School of Cyber Science and Engineering Southeast UniversityNanjing 211189China

In this paper,the optimal control of non-linear switching system is investigated without knowing the system ***,the Hamilton-Jacobi-Bellman(HJB)equation is derived with the consideration of hybrid action ***,a novel data-based hybrid Q-learning(HQL)algorithm is proposed to find the optimal solution in an iterative *** addition,the theoretical analysis is provided to illustrate the convergence and optimality of the proposed ***,the algorithm is implemented with the actor-critic(AC)structure,and two linear-in-parameter neural networks are utilized to approximate the *** results validate the effectiveness of the data-driven method.

关键词： switching system hybrid action space optimal control reinforcement learning hybrid Q-learning(HQL)

Event-triggered receding horizon control via actor-critic design

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Science China(Information Sciences) 2020年第5期63卷 131-145页

作者： lu dong Xin YUAN Changyin SUN School of Automation Southeast University College of Electronics and Information Engineering Tongji University Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSoutheast University

In this paper, we propose a novel event-triggered near-optimal control for nonlinear continuoustime systems. The receding horizon principle is utilized to improve the system robustness and obtain better dynamic control performance. In the proposed structure, we first decompose the infinite horizon optimal control into a series of finite horizon optimal problems. Then a learning strategy is adopted, in which an actor network is employed to approximate the cost function and an critic network is used to learn the optimal control law in each finite horizon. Furthermore, in order to reduce the computational cost and transmission cost, an event-triggered strategy is applied. We design an adaptive trigger condition, so that the signal transmissions and controller updates are conducted in an aperiodic way. Detailed stability analysis shows that the nonlinear system with the developed event-triggered optimal control policy is asymptotically *** results on a single-link robot arm with different noise types have demonstrated the effectiveness of the proposed method.

关键词： event-triggered control receding horizon control actor-critic design optimal control nonlinear systems neural networks

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外泌体提取及提高外泌体产量研究进展

中国医药生物技术 2024年第1期19卷 57-61页

作者：杨艾鲁卫东昆明医科大学药学院暨云南省天然药物药理重点实验室云南650500

外泌体是由细胞分泌的一种细胞外囊泡亚型的生物聚合物,参与一系列生理和病理反应,临床应用前景极具潜力。外泌体来源广泛,几乎所有细胞均可分泌。但由于外泌体体积小、密度低,目前暂无公认的方法能够同时实现外泌体快速、高效、高纯度... 详细信息

外泌体是由细胞分泌的一种细胞外囊泡亚型的生物聚合物,参与一系列生理和病理反应,临床应用前景极具潜力。外泌体来源广泛,几乎所有细胞均可分泌。但由于外泌体体积小、密度低,目前暂无公认的方法能够同时实现外泌体快速、高效、高纯度、无损伤的提取,导致产量低下,限制了临床应用,因此高效获得外泌体,提高外泌体产量对推动外泌体的临床应用尤为重要。具有脂质双分子层的脂质体利用其与外泌体结构相似的特性,能够在一定程度上提高外泌体的产量,故本文针对外泌体形成过程的各个阶段,对提高外泌体产量的方法进行综述。

关键词：外泌体产量脂质体分泌机制

Data-Based Optimal Tracking of Autonomous Nonlinear Switching Systems

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IEEE/CAA Journal of Automatica Sinica 2021年第1期8卷 227-238页

作者： Xiaofeng Li lu dong Changyin Sun the School of Automation Southeast UniversityNanjing 210096 the Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSoutheast UniversityNanjing 210096China the College of Electronics and Information Engineering Tongji UniversityShanghai 201804China

In this paper,a data-based scheme is proposed to solve the optimal tracking problem of autonomous nonlinear switching *** system state is forced to track the reference signal by minimizing the performance ***,the problem is transformed to solve the corresponding Bellman optimality equation in terms of the Q-function(also named as action value function).Then,an iterative algorithm based on adaptive dynamic programming(ADP)is developed to find the optimal solution which is totally based on sampled *** linear-in-parameter(LIP)neural network is taken as the value function *** the presence of approximation error at each iteration step,the generated approximated value function sequence is proved to be boundedness around the exact optimal solution under some verifiable ***,the effect that the learning process will be terminated after a finite number of iterations is investigated in this paper.A sufficient condition for asymptotically stability of the tracking error is ***,the effectiveness of the algorithm is demonstrated with three simulation examples.

关键词： Adaptive dynamic programming approximation error data-based control Q-learning switching system

Day-ahead scheduling based on reinforcement learning with hybrid action space

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Journal of Systems Engineering and Electronics 2022年第3期33卷 693-705页

作者： CAO Jingyu dong lu SUN Changyin School of Automation Southeast UniversityNanjing 210096China School of Cyber Science and Engineering Southeast UniversityNanjing 211189China

Driven by the improvement of the smart grid,the active distribution network(ADN)has attracted much attention due to its characteristic of active *** making full use of electricity price signals for optimal scheduling,the total cost of the ADN can be ***,the optimal dayahead scheduling problem is challenging since the future electricity price is ***,in ADN,some schedulable variables are continuous while some schedulable variables are discrete,which increases the difficulty of determining the optimal scheduling *** this paper,the day-ahead scheduling problem of the ADN is formulated as a Markov decision process(MDP)with continuous-discrete hybrid action ***,an algorithm based on multi-agent hybrid reinforcement learning(HRL)is proposed to obtain the optimal scheduling *** proposed algorithm adopts the structure of centralized training and decentralized execution,and different methods are applied to determine the selection policy of continuous scheduling variables and discrete scheduling *** simulation experiment results demonstrate the effectiveness of the algorithm.

关键词： day-ahead scheduling active distribution network(ADN) reinforcement learning hybrid action space

A Survey on Algorithms for Computing Comprehensive Gröbner Systems and Comprehensive Gröbner Bases

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Journal of Systems Science & Complexity 2019年第1期32卷 234-255页

作者： lu dong SUN Yao WANG Dingkang KLMM Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences SKLOIS Institute of Information EngineeringChinese Academy of Sciences

Weispfenning in 1992 introduced the concepts of comprehensive Gr?bner system/basis of a parametric polynomial system, and he also presented an algorithm to compute them. Since then,this research ?eld has attracted much attention over the past several decades, and many effcient algorithms have been proposed. Moreover, these algorithms have been applied to many different ?elds,such as parametric polynomial equations solving, geometric theorem proving and discovering, quanti?er elimination, and so on. This survey brings together the works published between 1992 and 2018, and we hope that this survey is valuable for this research area.

关键词： Comprehensive Gröbner basis comprehensive Gröbner system discovering geometric theorems mechanically parametric polynomial system quantifier elimination

Prototype for logging system calls and its overhead analysis

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Journal of Systems Engineering and Electronics 2007年第3期18卷 661-666,F0003页

作者： Meng Jiangtao lu Xianliang dong Guishan School of Computer Science and Engineering Univ. of Electronic Science and Technology of China Chendu 610054 P. R. China

With the capability of the virtual machine monitor, a novel approach for logging system activities is designed. In the design, the guest operating system runs on the virtual machine monitor as non-privileged mode. The redirecting and monitoring modules are added into the virtual machine monitor. When a guest application is calling a system call, it is trapped and redirected from the least privileged level into the virtual machine monitor running in the most privileged level. After logging is finished. it returns to the guest operating system running in the more privileged level and starts the system call. Compared with the traditional methods for logging system activities, the novel method makes it more difficult to destroy or tamper the logs. The preliminary evaluation shows that the prototype is simple and efficient.

关键词： virtual machine monitor virtual monitor Xen guest operating system hyper call system call.