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Parallel system Based Quantitative Assessment and Self-evolution for Artificial Intelligence of Active Power Corrective Control

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CSEE Journal of Power and Energy systems 2024年第1期10卷 13-28页

作者： Tianyun Zhang Jun Zhang Feiyue Wang Peidong Xu Tianlu Gao Haoran Zhang Ruiqi Si School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072HubeiChina State key laboratory for management and Control of complex system Institute of AutomationChinese Academy of SciencesBeijing 100190China

In artificial intelligence(AI)based-complex power system management and control technology,one of the urgent tasks is to evaluate AI intelligence and invent a way of autonomous intelligence evolution.However,there is,currently,nearly no standard technical framework for objective and quantitative intelligence evaluation.In this article,based on a parallel system framework,a method is established to objectively and quantitatively assess the intelligence level of an AI agent for active power corrective control of modern power systems,by resorting to human intelligence evaluation theories.On this basis,this article puts forward an AI self-evolution method based on intelligence assessment through embedding a quantitative intelligence assessment method into automated reinforcement learning(AutoRL)systems.A parallel system based quantitative assessment and self-evolution(PLASE)system for power grid corrective control AI is thereby constructed,taking Bayesian Optimization as the measure of AI evolution to fulfill autonomous evolution of AI under guidance of their intelligence assessment results.Experiment results exemplified in the power grid corrective control AI agent show the PLASE system can reliably and quantitatively assess the intelligence level of the power grid corrective control agent,and it could promote evolution of the power grid corrective control agent under guidance of intelligence assessment results,effectively,as well as intuitively improving its intelligence level through selfevolution.

关键词： AI quantitative intelligence assessment and self-evolution automated reinforcement learning Bayesian optimization corrective control parallel system

A probe into the acid deposition mitigation path in China over the last four decades and beyond

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National Science Review 2024年第4期11卷 84-92页

作者： Qian Yu Xiaodong Ge Haotian Zheng Jia Xing Lei Duan Dongwei Lv Dian Ding Zhaoxin Dong Yisheng Sun Posch Maximilian Danni Xie Yu Zhao Bin Zhao Shuxiao Wang Jan Mulder Thorj?rn Larssen Jiming Hao State key laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua University State key laboratory of Pollution Control &Resource Reuse and School of the Environment Nanjing University State Environmental Protection key laboratory of Sources and Control of Air Pollution complex School of EnvironmentTsinghua University International Institute for Applied system analysis(IIASA) School of Land Engineering Chang'an University Faculty of Environmental Sciences and Natural Resource management Norwegian University of Life Sciences Norwegian Institute for Water Research

China currently has the highest acid deposition globally, yet research on its status, impacts, causes and controls is lacking. Here, we compiled data and calculated critical loads regarding acid deposition. The results showed that the abatement measures in China have achieved a sharp decline in the emissions of acidifying pollutants and a continuous recovery of precipitation p H, despite the drastic growth in the economy and energy consumption. However, the risk of ecological acidification and eutrophication showed no significant decrease. With similar emission reductions, the decline in areas at risk of acidification in China(7.0%) lags behind those in Europe(20%) or the USA(15%). This was because, unlike Europe and the USA, China's abatement strategies primarily target air quality improvement rather than mitigating ecological impacts. Given that the area with the risk of eutrophication induced by nitrogen deposition remained at 13%of the country even under the scenario of achieving the dual targets of air quality and carbon dioxide mitigation in 2035, we explored an enhanced ammonia abatement pathway. With a further 27% reduction in ammonia by 2035, China could largely eliminate the impacts of acid deposition. This research serves as a valuable reference for China's future acid deposition control and for other nations facing similar challenges.

关键词： acid deposition critical loads acidification eutrophication ammonia abatement

Estimating wheat spike-leaf composite indicator(SLI)dynamics by coupling spectral indices and machine learning

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The Crop Journal 2024年第3期12卷 927-937页

作者： Haiyu Tao Ruiheng Zhou Yining Tang Wanyu Li Xia Yao Tao Cheng Yan Zhu Weixing Cao Yongchao Tian National Engineering and Technology Center for Information Agriculture Key Laboratory of Crop System Analysis and Decision MakingMinistry of Agriculture and Rural AffairsJiangsu Key Laboratory for Information AgricultureNanjing Agricultural UniversityNanjing 210095JiangsuChina

The contribution of spike photosynthesis to grain yield(GY)has been overlooked in the accurate spectral prediction of yield.Thus,it’s essential to construct and estimate a yield-related phenotypic trait considering spike photosynthesis.Based on field and spectral reflectance data from 19 wheat cultivars under two nitrogen fertilization conditions in two years,our objectives were to(i)construct a yield-related phenotypic trait(spike–leaf composite indicator,SLI)accounting for the contribution of the spike to photosynthesis,(ii)develop a novel spectral index(enhanced triangle vegetation index,ETVI3)sensitive to SLI,and(iii)establish and evaluate SLI estimation models by integrating spectral indices and machine learning algorithms.The results showed that SLI was sensitive to nitrogen fertilizer and wheat cultivar variation as well as a better predictor of yield than the leaf area index.ETVI3 maintained a strong correlation with SLI throughout the growth stage,whereas the correlations of other spectral indices with SLI were poor after spike emergence.Integrating spectral indices and machine learning algorithms improved the estimation accuracy of SLI,with the most accurate estimates of SLI showing coefficient of determination,root mean square error(RMSE),and relative RMSE values of 0.71,0.047,and 26.93%,respectively.These results provide new insights into the role of fruiting organs for the accurate spectral prediction of GY.This high-throughput SLI estimation approach can be applied for wheat yield prediction at whole growth stages and may be assisted with agronomical practices and variety selection.

关键词： Wheat spike photosynthesis Yield-related phenotypic trait Spectral indices Machine learning Estimation

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Fast measurement and prediction method for electromagnetic susceptibility of receiver

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Journal of systems Engineering and Electronics 2024年第2期35卷 275-285页

作者： CHEN Yan LU Zhonghao LIU Yunxia State key laboratory of complex Electromagnetic Environment Effects on Electronics and Information system College of Electronic Science and TechnologyNational University of Defense TechnologyChangsha 410073China State key laboratory of Astronautic Dynamics Xi’an 710043China

Aiming at evaluating and predicting rapidly and accurately a high sensitivity receiver’s adaptability in complex electromagnetic environments,a novel testing and prediction method based on dual-channel multi-frequency is proposed to improve the traditional two-tone test.Firstly,two signal generators are used to generate signals at the radio frequency(RF)by frequency scanning,and then a rapid measurement at the intermediate frequency(IF)output port is carried out to obtain a huge amount of sample data for the subsequent analysis.Secondly,the IF output response data are modeled and analyzed to construct the linear and nonlinear response constraint equations in the frequency domain and prediction models in the power domain,which provide the theoretical criteria for interpreting and predicting electromagnetic susceptibility(EMS)of the receiver.An experiment performed on a radar receiver confirms the reliability of the method proposed in this paper.It shows that the interference of each harmonic frequency and each order to the receiver can be identified and predicted with the sensitivity model.Based on this,fast and comprehensive evaluation and prediction of the receiver’s EMS in complex environment can be efficiently realized.

关键词： electromagnetic susceptibility(EMS) receiver dualchannel multi-frequency nonlinear response frequency domain power domain

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Relaxed Stability Criteria for Time-Delay systems:A Novel Quadratic Function Convex Approximation Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 996-1006页

作者： Shenquan Wang Wenchengyu Ji Yulian Jiang Yanzheng Zhu Jian Sun College of Electrical and Electronic Engineering Changchun University of TechnologyChangchun 130012China the College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China key laboratory of complex systems Intelligent Control and decision Beijing Institute of TechnologyBeijing 100081China

This paper develops a quadratic function convex approximation approach to deal with the negative definite problem of the quadratic function induced by stability analysis of linear systems with time-varying delays.By introducing two adjustable parameters and two free variables,a novel convex function greater than or equal to the quadratic function is constructed,regardless of the sign of the coefficient in the quadratic term.The developed lemma can also be degenerated into the existing quadratic function negative-determination(QFND)lemma and relaxed QFND lemma respectively,by setting two adjustable parameters and two free variables as some particular values.Moreover,for a linear system with time-varying delays,a relaxed stability criterion is established via our developed lemma,together with the quivalent reciprocal combination technique and the Bessel-Legendre inequality.As a result,the conservatism can be reduced via the proposed approach in the context of constructing Lyapunov-Krasovskii functionals for the stability analysis of linear time-varying delay systems.Finally,the superiority of our results is illustrated through three numerical examples.

关键词： Equivalent reciprocal combination technique quadratic function convex approximation approach stability timevarying delay

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A novel domain decomposition-based model for efficient dynamic predictions of large composite machine tools

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Science China Technological Sciences 2024年第6期67卷 1765-1782页

作者： YU YangBo JI Yu Lei CHEN YanRen XU Kun BI QingZhen State key laboratory of Mechanical system and Vibration School of Mechanical EngineeringShanghai Jiao Tong University

We propose a large combined moving component composed of carbon fiber reinforced polymer(CFRP) laminates for making lightweight machine tools with high dynamic performance. The accurate dynamic prediction of composite machine tools is essential for the new generation machine tool. This paper aims to address two challenges in numerical dynamic modeling and the design of composite machine tools to enhance development efficiency.(1) Anisotropic composite laminates, which form the composite machine tool, exhibit coupling in various directions. We propose the generalized continuity condition of the boundary to tackle this dynamic modeling challenge.(2) Composite machine tools feature numerous composite-metal coupled structures.The mechanical model correction of isotropic metals is performed to address their dynamics. We take the example of a five-axis gantry machine tool with composite moving parts, establish a dynamic model for efficient prediction, and verify it through simulation and experimentation. The proposed method yields remarkable results, with an average relative error of only 3.85% in modal frequency prediction and a staggering 99.7% reduction in solution time compared to finite element analysis. We further discuss the dynamic performance of the machine tool under varied stacking angles and layer numbers of the composite machine tool. We propose general design criteria for composite machine tools to consider the modal frequency and manufacturing cost of machine tools.

关键词： machine tool dynamics carbon fiber reinforced polymer composite laminates

Dynamics modeling and electromechanical coupling characteristics analysis of cage induction motors

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Science China(Technological Sciences) 2024年第3期67卷 709-724页

作者： ZHOU ZiWei CHEN ZaiGang ZHAI WanMing State key laboratory of Rail Transit Vehicle system Southwest Jiaotong UniversityChengdu 610031China

Induction motors, as typical electromechanical energy conversion devices, have received limited attention in previous studies on electromechanical coupling vibrations, precise modeling, and the use of electromechanical coupling effects for fault diagnosis and condition assessment in motor drive systems. This study proposes a comprehensive model of cage induction motors that integrates the multiple coupled circuit model with a rotor-bearing dynamics model. The model accounts for the linear increase in the magnetomotive force across the slot and incorporates the skidding characteristics of bearings in the rotor-bearing system. By calculating the time-varying mutual inductance parameters based on the air-gap distribution in the vibration environment, the electromechanical coupling vibration of the cage motor is investigated. Furthermore, this study examines the electromechanical coupling vibration characteristics influenced by various factors, including bearing clearances, radial loads, and the vertical excitation frequencies of the stators. The results show that the proposed model improves the excitation inputs for the electrical and mechanical systems of the motor compared with conventional models. Increased bearing clearance and radial load affect the current and torque similarly but have opposite effects on the slip ratio. This study provides a deeper understanding of electromechanical coupling mechanisms and facilitates the use of such phenomena for fault diagnosis and condition assessment in motor-driven systems.

关键词： cage induction motors rotor-bearing dynamics mutual inductance electromechanical testing current signal analysis

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An optimized method of culturing neurons based on polyacrylamide gel

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Biophysics Reports 2024年第1期10卷 41-47页

作者： Yongjing Qiao Jihong Gong Ziqi Jin Yiting Tu Xiaofei Yang key laboratory of Cognitive Science Hubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis & Treatment Laboratory of Membrane Ion Channels and Medicine College of Biomedical Engineering SouthCentral Minzu University

Substrate stiffness is a microenvironment with a certain stiffness constructed by the extracellular matrix and adjacent cells, which plays an important role in the growth and development of cells and tissue formation. Studies have indicated that the stiffness of the brain is about 0.1–1 kPa. The physiological and pathological processes of the nervous system are mediated by the substrate stiffness that the neurons suffer. However, how substrate stiffness regulates these processes remains to be studied. Culturing neurons on substrates with different stiffness in vitro is one of the best methods to study the role of stiffness in regulating neuronal development and activity. In this study, by changing the preparation time and the activation time of polyacrylamide gel, we provide an improved method that achieves a low toxic substrate environment for better primary neuron adhesion and development. Hope that this method is convenient for those studying the role of substrate stiffness in neurons.

关键词： Polyacrylamide gel Neuron culture Cell adhesion Neural cell development

Improving error-correcting capability in DNA digital storage via soft-decision decoding

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National Science Review 2024年第2期11卷 135-144页

作者：丁璐璐伍世刚候志浩李阿伦许亚苹冯虎潘玮华阮珏 Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural Sciences Guangdong Provincial key laboratory of Plant Molecular Breeding State Key Laboratory for Conservation and Utilization of Subtropical Agro-BioresourcesSouth China Agricultural University

Error-correcting codes(ECCs) employed in the state-of-the-art DNA digital storage(DDS) systems suffer from a trade-off between error-correcting capability and the proportion of redundancy. To address this issue, in this study, we introduce soft-decision decoding approach into DDS by proposing a DNA-specific error prediction model and a series of novel strategies. We demonstrate the effectiveness of our approach through a proof-of-concept DDS system based on Reed-Solomon(RS) code, named as Derrick. Derrick shows significant improvement in error-correcting capability without involving additional redundancy in both in vitro and in silico experiments, using various sequencing technologies such as Illumina, Pac Bio and Oxford Nanopore Technology(ONT). Notably, in vitro experiments using ONT sequencing at a depth of 7× reveal that Derrick, compared with the traditional hard-decision decoding strategy, doubles the error-correcting capability of RS code, decreases the proportion of matrices with decoding-failure by 229-fold, and amplifies the potential maximum storage volume by impressive 32 388-fold. Also, Derrick surpasses ‘state-of-the-art' DDS systems by comprehensively considering the information density and the minimum sequencing depth required for complete information recovery. Crucially, the soft-decision decoding strategy and key steps of Derrick are generalizable to other ECCs' decoding algorithms.

关键词： DNA digital storage (DDS) error-correcting code (ECC) soft-decision decoding error-correcting capability storage volume