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Robust reinforcement learning with UUB guarantee for safe motion control of autonomous robots

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Science China(Technological Sciences) 2024年第1期67卷 172-182页

作者： ZHANG RuiXian HAN YiNing SU Man LIN ZeFeng LI HaoWei ZHANG LiXian school of Astronautics Harbin Institute of TechnologyHarbin 150001China school of management Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Tracking and Telecommunication Technology Beijing 100094China

This paper addresses the issue of safety in reinforcement learning(RL)with disturbances and its application in the safety-constrained motion control of autonomous *** tackle this problem,a robust Lyapunov value function(rLVF)is *** rLVF is obtained by introducing a data-based LVF under the worst-case disturbance of the observed *** the rLVF,a uniformly ultimate boundedness criterion is *** criterion is desired to ensure that the cost function,which serves as a safety criterion,ultimately converges to a range via the policy to be ***,to mitigate the drastic variation of the rLVF caused by differences in states,a smoothing regularization of the rLVF is *** train policies with safety guarantees under the worst disturbances of the observed states,an off-policy robust RL algorithm is *** proposed algorithm is applied to motion control tasks of an autonomous vehicle and a cartpole,which involve external disturbances and variations of the model parameters,*** experimental results demonstrate the effectiveness of the theoretical findings and the advantages of the proposed algorithm in terms of robustness and safety.

关键词： motion control reinforcement learning robustness stability

Preparation and performance improvement of a dual-component microcapsule self-healing system for silicone rubber insulating material

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High Voltage 2024年第2期9卷 453-465页

作者： Mingzhe Li Bin Cao Fanghui Yin Hongwei Mei Liming Wang Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhenChina

A key factor limiting the development of silicone rubber insulating materials is their short service life in harsh operating *** establishment of a self-healing system is desired to improve the long-term operational performance of silicone rubber and effectively extend its service *** this study,poly(urea-formaldehyde)microcapsules containing polydimethylsiloxane healing agents are prepared and a dual-component microcapsule self-healing system for silicone rubber material is established and *** addition,the key factors affecting the self-healing performance(such as microcapsule size,rupture rate,and microcapsule doping amount)are *** is found that when SYLGARDTM 184 is used as the healing agent and matrix,with a 4:6(A:B)doping ratio of dual-component microcapsules and 20 phr doping amount,the self-healing efficiency is approximately 51%.Furthermore,increasing the microcapsule rupture rate and the interface strength between the healing agent and the matrix can effectively improve the self-healing *** relationships between key factors and self-healing performance are theoretically *** on the relationships,the microcapsule self-healing system can be appropriately *** results of this paper can provide a reference for the development of long-life silicone rubber insulating materials.

关键词： service rubber performance

Recursive filtering of multi-rate cyber-physical systems with unknown inputs under adaptive event-triggered mechanisms

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 250-259页

作者： Ying SUN Miaomiao FU Jingyang MAO Guoliang WEI Business school University of Shanghai for Science and TechnologyShanghai200093China Shanghai Caoyang Vocational school Shanghai200333China school of Electrical and Electronic Engineering Shanghai Institute of TechnologyShanghai201418China school of Intelligent Emergency management University of Shanghai for Science and TechnologyShanghai200093China

Cyber-physical systems(CPSs)take on the characteristics of both multiple rates of information collection and processing and the dependency on information *** purpose of this paper is to develop a joint recursive filtering scheme that estimates both unknown inputs and system states for multi-rate CPSs with unknown *** cyberspace,the information transmission between the local joint filter and the sensors is governed by an adaptive event-triggered ***,the desired parameters of joint filters are determined by a set of algebraic matrix equations in a recursive way,and a sufficient condition verifying the boundedness of filtering error covariance is found by resorting to some algebraic operation.A state fusion estimation scheme that uses local state estimation is proposed based on the covariance intersection(CI)based fusion ***,an illustrative example demonstrates the effectiveness of the proposed adaptive event-triggered recursive filtering algorithm.

关键词： Cyber-physical systems Multi-rate Joint recursive filtering Adaptive event-triggered mechanisms Unknown inputs

Performance evaluation of seven multi-label classification methods on real-world patent and publication datasets

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Journal of Data and Information Science 2024年第2期9卷 81-103页

作者： Shuo Xu Yuefu Zhang Xin An Sainan Pi College of Economics and management Beijing University of TechnologyBeijing 100124China school of Economics&management Beijing Forestry UniversityBeijing 100083China

Purpose:Many science,technology and innovation(STI)resources are attached with several different *** assign automatically the resulting labels to an interested instance,many approaches with good performance on the benchmark datasets have been proposed for multi-label classification task in the ***,several open-source tools implementing these approaches have also been ***,the characteristics of real-world multi-label patent and publication datasets are not completely in line with those of benchmark ***,the main purpose of this paper is to evaluate comprehensively seven multi-label classification methods on real-world *** limitations:Three real-world datasets differ in the following aspects:statement,data quality,and ***,open-source tools designed for multi-label classification also have intrinsic differences in their approaches for data processing and feature selection,which in turn impacts the performance of a multi-label classification *** the near future,we will enhance experimental precision and reinforce the validity of conclusions by employing more rigorous control over variables through introducing expanded parameter *** implications:The observed Macro F1 and Micro F1 scores on real-world datasets typically fall short of those achieved on benchmark datasets,underscoring the complexity of real-world multi-label classification *** leveraging deep learning techniques offer promising solutions by accommodating the hierarchical relationships and interdependencies among *** ongoing enhancements in deep learning algorithms and large-scale models,it is expected that the efficacy of multi-label classification tasks will be significantly improved,reaching a level of practical utility in the foreseeable ***/value:(1)Seven multi-label classification methods are comprehensively compared on three real-world datasets.(2)The TextCNN and

关键词： Multi-label classification Real-World datasets Hierarchical structure Classification system Label correlation Machine learning

Development of D_α band symmetrical visible optical diagnostic for boundary reconstruction on EAST tokamak

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Plasma Science and Technology 2024年第2期26卷 44-53页

作者：陈明沈飊 Shinichiro KADO 郭笔豪陈大龙蔡福瑞肖炳甲 Hefei Institutes of Physical Science Chinese Academy of SciencesHefei 230031People's Republic of China Science Island Branch Graduate School of University of Science and Technology of ChinaHefei 230026People's Republic of China Institute of Advanced Energy Kyoto UniversityUji 611-0011Japan graduate school of Energy Science Kyoto UniversityUji 611-0011Japan

To investigate the potential of utilizing visible spectral imaging for controlling the plasma boundary shape during stable operation of plasma in future tokamak, a D_α band symmetric visible light diagnostic system was designed and implemented on the Experimental Advanced Superconducting Tokamak(EAST). This system leverages two symmetric optics for joint plasma imaging. The optical system exhibits a spatial resolution less than 2 mm at the poloidal cross-section, distortion within the field of view below 10%, and relative illumination of 91%.The high-quality images obtained enable clear observation of both the plasma boundary position and the characteristics of components within the vacuum vessel. Following system calibration and coordinate transformation, the image coordinate boundary features are mapped to the tokamak coordinate system. Utilizing this system, the plasma boundary was reconstructed, and the resulting representation showed alignment with the EFIT(Equilibrium Fitting) results. This underscores the system's superior performance in boundary reconstruction applications and provides a diagnostic foundation for boundary shape control based on visible spectral imaging.

关键词： visible optical diagnostic plasma boundary reconstruction EAST

The Role of Nudging in systems

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Journal of systems Science and Information 2024年

作者： Qiguo GONG Hai YANG University of Chinese Academy of Sciences school of Economics and management

The 2017 Nobel Prize in Economics was awarded to Thaler, whose concept of nudges has been widely used. Although existing research has proposed numerous nudging strategies, there is no research comprehensively examining the role of nudging,resulting limited attention across various *** fill this gap, this study aims to present how to analyze the role of nudges in the system using a systems thinking approach. The analysis indicates that nudges have a multiplier effect in the system and can achieve significant results at a small cost. We use three cases to analyze the effective impact of nudges on decision making: changing the default setting in organ donation, providing the check list to avoid mistakes in surgery, and the approach to prevent the coronavirus epidemic applied in China.

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A Hydrogen-Bonded,Hexagonally Networked,Layered Framework with Large Aperture Designed by Structural Synchronization of a Macrocycle and Supramolecular Synthon

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Precision Chemistry 2024年第5期2卷 221-228页

作者： Hiroki Yoshimura Ryusei Oketani Miki Naruoka Norimitsu Tohnai Ichiro Hisaki Division of Chemistry Graduate School of Engineering ScienceOsaka UniversityToyonakaOsaka 560-8531Japan Department of Applied Chemistry Graduate School of EngineeringOsaka UniversitySuitaOsaka 565-0871Japan

To develop porous organic frameworks,precise control of the stacking manner of two-dimensional porous motifs and structural characterization of the resultant framework are *** these points of view,porous molecular crystals formed through reversible intermolecular hydrogen bonds,such as;hydrogen-bonded organic frameworks(HOFs),can provide deep insight because of their high crystallinity,affording single-crystalline X-ray diffraction *** this study,we demonstrate that the stacking manner of hydrogen-bonded hexagonal network(HexNet)sheets can be controlled by synchronizing a homological triangular macrocyclic tecton and a hydrogen-bonded cyclic supramolecular synthon called the phenylene triangle.A structure of the resultant HOF was crystallographically characterized and revealed to have a large channel aperture of 2.4 *** HOF also shows thermal stability up to 290°C,which is higher than that of the conventional HexNet frameworks.

关键词： hydrogen-bonded organicframeworks hexagonalnetwork macrocycle carboxylicacid porosity

22 kW near-diffraction-limited Yb:YAG slab laser amplifier without adaptive optics correction

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Chinese Optics Letters 2024年第3期22卷 65-70页

作者：汪丹何平周唐建李密邬映臣王亚楠尚建力高清松张凯唐淳朱日宏 school of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China Institute of Applied Electronics China Academy of Engineering PhysicsMianyang 430079China graduate school of China Academy of Engineering Physics Beijing 100193China

A high-power CW Yb:YAG slab laser amplifier with no adaptive optics correction has been experimentally *** room temperature,the amplifier emits a power of 22 kW with an average beam quality(β)of less than 3 in 0.5 *** our knowledge,this is the brightest slab laser without closed-loop adaptive optics demonstrated to *** addition,an extracted power of 17 kW with an optical extraction efficiency of 33%,corresponding to a residual optical path difference of less than 0.5μm,is achieved with the single Yb:YAG slab gain *** slab gain module has the potential to be scalable to higher powers while maintaining good beam *** makes a high-power solid-state laser system simpler and more robust.

关键词： laser amplifier Yb:YAG slab laser surface quality pumping uniformity

Does Green Food Certification promote agri-food export quality?Evidence from China

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Journal of Integrative Agriculture 2024年第3期23卷 1061-1074页

作者： Ping Wei Hongman Liu Chaokai Xu Shibin Wen College of Economics and management China Agricultural UniversityBeijing 100083China school of Public Affairs Zhejiang UniversityHangzhou 310058China

The construction of a food certification system plays a vital role in upgrading export quality, which previous studies have largely overlooked. We match China's industry-level data of Green Food Certification with its HS6-digit export data of agri-food products to quantify the impact of Green Food Certification on export quality. We identify the significant and positive effect of Green Food Certification on export quality. The 2SLS estimation based on instrumental variables and a range of robustness checks confirm the validity and robustness of the benchmark conclusions. Further analysis discloses that Green Food Certification improves export quality by raising agricultural production efficiency and brand premiums. Heterogeneity analysis shows that the effect of Green Food Certification varies across regions, notably improving the quality of agri-food products exported to developed regions and regions with high levels of import supervision. Furthermore, among various product types, Green Food Certification significantly improves the export quality of primary products and products vulnerable to non-tariff measures. The above findings could guide the future development of agri-food quality certification systems, potentially leading to a transformation and promotion of the agri-food trade.

关键词： Green Food Certification agri-food products green transformation export quality food labeling