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Novel intelligent reasoning system for tool wear prediction and parameter optimization in intelligent milling

Advances in Manufacturing 2024年第1期12卷 76-93页

作者： Long-Hua Xu Chuan-zhen Huang zhen wang Han-Lian Liu Shui-Quan Huang Jun wang School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiPeople’s Republic of China Center for Advanced Jet Engineering Technologies(CaJET) Key Laboratory of High-efficiency and Clean Mechanical Manufacture(Ministry of Education)National Experimental Teaching Demonstration Center for Mechanical Engineering(Shandong University)School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China Institute of Manufacturing Technology Guangdong University of TechnologyGuangzhou510006People’s Republic of China

Accurate intelligent reasoning systems are vital for intelligent manufacturing.In this study,a new intelligent reasoning system was developed for milling processes to accurately predict tool wear and dynamically optimize machining parameters.The developed system consists of a self-learning algorithm with an improved particle swarm optimization(IPSO)learning algorithm,prediction model determined by an improved case-based reasoning(ICBR)method,and optimization model containing an improved adaptive neural fuzzy inference system(IANFIS)and IPSO.Experimental results showed that the IPSO algorithm exhibited the best global convergence performance.The ICBR method was observed to have a better performance in predicting tool wear than standard CBR methods.The IANFIS model,in combination with IPSO,enabled the optimization of multiple objectives,thus generating optimal milling parameters.This paper offers a practical approach to developing accurate intelligent reasoning systems for sustainable and intelligent manufacturing.

关键词： Improved particle swarm optimization(IPSO)algorithm Improved case-based reasoning(ICBR)method Adaptive neural fuzzy inference system(ANFIS)model Tool wear prediction Intelligent manufacturing

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Cavity-enhanced photoacoustic dual-comb spectroscopy

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Light(Science & Applications) 2024年第4期13卷 610-618页

作者： zhen wang Qinxue Nie Haojia Sun Qiang wang Simone Borri Paolo De Natale Wei Ren Department of Mechanical and Automation Engineering The Chinese University of Hong KongNew TerritoriesHong Kong SARChina. State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences130033 ChangchunChina. CNRINO-Istituto Nazionale di Ottica and LENS-European Laboratory for Nonlinear Spectroscopy50019 Sesto FiorentinoItaly

Photoacoustic dual-comb spectroscopy(DCS),converting spectral information in the optical frequency domain to the audio frequency domain via multi-heterodyne beating,enables background-free spectral measurements with high resolution and broad bandwidth.However,the detection sensitivity remains limited due to the low power of individual comb lines and the lack of broadband acoustic resonators.Here,we develop cavity-enhanced photoacoustic DCS,which overcomes these limitations by using a high-finesse optical cavity for the power amplification of dual-frequency combs and a broadband acoustic resonator with a flat-top frequency response.We demonstrate high-resolution spectroscopic measurements of trace amounts of C2H2,NH3 and CO in the entire telecommunications C-band.The method shows a minimum detection limit of 0.6 ppb C2H2 at the measurement time of 100 s,corresponding to the noise equivalent absorption coefficient of 7×10−10 cm−1.The proposed cavityenhanced photoacoustic DCS may open new avenues for ultrasensitive,high-resolution,and multi-species gas detection with widespread applications.

关键词： individual cavity spectroscopy

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Decentralized Primary Frequency Regulation for Hybrid Multi-terminal Direct Current Power Systems Considering Multi-source Enhancement

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 958-970页

作者： Jialiang Wu zhen wang Ruixu Liu Yu Shan Chenxuan wang the College of Electrical Engineering Zhejiang University IEEE the Economic Research Institute of State Grid Zhejiang Electric Power Co. Ltd.

Hybrid multi-terminal direct current(MTDC) transmission technology has been a research focus, and primary frequency regulation(FR) improvement in the receiving-end system is one of the problems to be solved. This paper presents a decentralized primary FR scheme for hybrid MTDC power systems considering multi-source enhancement to help suppress frequency disturbance in the receiving-end systems. All the converters only need local frequency or DC voltage signal input to respond to system disturbance without communication or a control center, i. e., a decentralized control scheme. The proposed scheme can activate appropriate power sources to assist in FR in various system disturbance severities with fine-designed thresholds, ensuring sufficient utilization of each power source. To better balance FR performance and FR resource participation, an evaluation index is proposed and the parameter optimization problem is further conducted. Finally, the validity of the proposed scheme is verified by simulations in MATLAB/Simulink.

关键词： Frequency control HVDC transmission Voltage control Hybrid power systems Frequency conversion Voltage measurement Power system stability

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Partition-based Network Equivalent Method for Power System Subsynchronous Oscillation Analysis

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 313-320页

作者： Chenxuan wang Weimin zheng zhen wang Yangqing Dan Ping Ju the Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China the Economic Research Institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310016China the College of Energy and Electrical Engineering Hohai UniverstiyNanjing 211100China

Given large-scale modern power systems with pow er electronic converters,the numerical simulation with subsyn chronous oscillation(SSO)faces great challenges in engineering practice due to sharply enlarged modeling scale and high com putational burden.To reduce the modeling scale,network parti tion and equivalent becomes a vital technique in numerical sim ulations.Although several methods have been developed for net work equivalent,a generally accepted rule for network parti tion is still required.This paper proposes that the system can be partitioned into three parts,i.e.,the internal,the middle,and the external subsystems,in which the internal subsystem consists of all power electronic components,the middle subsys tem includes those selected AC dynamic components with de tailed models,and the remaining components and buses consti tute the external subsystem.The external subsystem is further represented by an equivalent RLC network determined by the frequency dependent network equivalent(FDNE)method.In the proposed method,the observability index and the electrical distance index are used to identify the interface between the middle and the external subsystems.Case studies based on a modified Hydro-Quebec system are used to verify the effective ness of the proposed method.

关键词： Electrical distance network equivalent subsyn chronous oscillation observability index

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Track-Pattern-Based Characteristics of Extratropical Transitioning Tropical Cyclones in the Western North Pacific

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Advances in Atmospheric Sciences 2024年第6期41卷 1251-1263页

作者： Hong HUANG Dan WU Yuan wang zhen wang Yu LIU College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China No.31631 Army of PLA Huizhou 516000China School of Atmospheric Sciences and Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing 210023China No.93721 Army of PLA Shuozhou 038300China

Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track patterns.The characteristics of the six hard-clustered ETCs with the highest membership coefficient are shown.Most tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these regions.Among landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one day.The frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four decades.The surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying ETCs.Our results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP.

关键词： Western North Pacific tropical cyclone extratropical transition fuzzy c-means clustering method

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Impact of sourdough fermentation on nutrient transformations in cereal-based foods:Mechanisms,practical applications,and health implications

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Grain & Oil Science and Technology 2024年第2期7卷 124-132页

作者： zhen wang Luyang wang State Key Laboratory of Crop Stress Adaptation and Improvement College of AgricultureHenan UniversityKaifeng 475004China

Sourdough is often considered a healthy choice and quality improver for use in cereal production due to its unique microbial composition and fermentation properties.During sourdough fermentation of cereals,biotransformation of nutrients occurs,resulting in notable changes to proteins,carbohydrates,fats,vitamins,and minerals.Each nutrient undergoes specific transformations,providing various advantages for human health.Proteins undergo hydrolysis to produce small molecular weight peptides and amino acids that are more easily digested and absorbed by the human body.Carbohydrates break down to improve the digestibility and absorption of cereals and lower the glycemic index.Fatty acids experience oxidation to produce new substances with health benefits.Additionally,the application of sourdough fermentation can enhance the texture,flavor,and nutritional value of cereal foods while also extending their shelf life and improving food safety.In conclusion,sourdough fermentation has a broad range of applications in cereal food processing.Further research is encouraged to investigate the mechanisms and processes of sourdough fermentation to develop even more nutritious,healthy,and flavorful cereal-based foods.

关键词： Sourdough fermentation Lactic acid bacteria Proteolysis Starch hydrolysis Low-GI Nutrients

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Ensemble successor representations for task generalization in offline-to-online reinforcement learning

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Science China(Information Sciences) 2024年第7期67卷 240-255页

作者： Changhong wang Xudong YU Chenjia BAI Qiaosheng ZHANG zhen wang Space Control and Inertial Technology Research Center Harbin Institute of Technology Shanghai Artificial Intelligence Laboratory Shenzhen Research Institute of Northwestern Polytechnical University School of Cybersecurity Northwestern Polytechnical University

In reinforcement learning(RL), training a policy from scratch with online experiences can be inefficient because of the difficulties in exploration. Recently, offline RL provides a promising solution by giving an initialized offline policy, which can be refined through online interactions. However, existing approaches primarily perform offline and online learning in the same task, without considering the task generalization problem in offline-to-online adaptation. In real-world applications, it is common that we only have an offline dataset from a specific task while aiming for fast online-adaptation for several tasks. To address this problem, our work builds upon the investigation of successor representations for task generalization in online RL and extends the framework to incorporate offline-to-online learning. We demonstrate that the conventional paradigm using successor features cannot effectively utilize offline data and improve the performance for the new task by online fine-tuning. To mitigate this, we introduce a novel methodology that leverages offline data to acquire an ensemble of successor representations and subsequently constructs ensemble Q functions. This approach enables robust representation learning from datasets with different coverage and facilitates fast adaption of Q functions towards new tasks during the online fine-tuning phase.Extensive empirical evaluations provide compelling evidence showcasing the superior performance of our method in generalizing to diverse or even unseen tasks.

关键词： offline reinforcement learning online fine-tuning task generalization successor representations ensembles

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An anti-collision algorithm for robotic search-and-rescue tasks in unknown dynamic environments

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 569-584页

作者： Yang CHEN Dianxi SHI Huanhuan YANG Tongyue LI zhen wang School of Computer Science Peking UniversityBeijing 100871China Tianjin Artificial Intelligence Innovation Center Tianjin 300457China Intelligent Game and Decision Lab Beijing 100071China College of Computer National University of Defense TechnologyChangsha 410073China

This paper deals with the search-and-rescue tasks of a mobile robot with multiple interesting targets in an unknown dynamic environment.The problem is challenging because the mobile robot needs to search for multiple targets while avoiding obstacles simultaneously.To ensure that the mobile robot avoids obstacles properly,we propose a mixed-strategy Nash equilibrium based Dyna-Q(MNDQ)algorithm.First,a multi-objective layered structure is introduced to simplify the representation of multiple objectives and reduce computational complexity.This structure divides the overall task into subtasks,including searching for targets and avoiding obstacles.Second,a risk-monitoring mechanism is proposed based on the relative positions of dynamic risks.This mechanism helps the robot avoid potential collisions and unnecessary detours.Then,to improve sampling efficiency,MNDQ is presented,which combines Dyna-Q and mixed-strategy Nash equilibrium.By using mixed-strategy Nash equilibrium,the agent makes decisions in the form of probabilities,maximizing the expected rewards and improving the overall performance of the Dyna-Q algorithm.Furthermore,a series of simulations are conducted to verify the effectiveness of the proposed method.The results show that MNDQ performs well and exhibits robustness,providing a competitive solution for future autonomous robot navigation tasks.

关键词： Search and rescue Reinforcement learning Game theory Collision avoidance Decision-making

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A Finite-Time Convergent Analysis of Continuous Action Iterated Dilemma

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 563-565页

作者： zhen wang Xiaoyue Jin Tao Zhang Dengxiu Yu Northwestern Polytechnical University

Dear Editor,In this letter, a finite-time convergent analysis of continuous action iterated dilemma(CAID) is proposed. In traditional evolutionary game theory, the strategy of the player is binary(cooperation or defec... 详细信息

关键词： lemma letter convergent

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S-scheme regulated Ni_(2)P-NiS/twinned Mn_(0.5)Cd_(0.5)S hetero-homojunctions for efficient photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第2期169卷 148-157页

作者： Qiqi Zhang zhen wang Yuhang Song Jun Fan Tao Sun Enzhou Liu School of Chemical Engineering/Xi’an Key Laboratory of Special Energy Materials Northwest UniversityXi’an 710069China

Effective bulk phase and surface charge separation is critical for charge utilization during the photo-catalytic energy conversion process.In this work,the ternary Ni_(2)P-NiS/twinned Mn_(0.5)Cd_(0.5)S(T-MCS)nanohybrids were successfully constructed via combining Ni_(2)P-NiS with T-MCS solid solution for visible light photocatalytic H_(2)evolution.T-MCS is composed of zinc blende Mn_(0.5)Cd_(0.5)S(ZB-MCS)and wurtzite Mn_(0.5)Cd_(0.5)S(WZ-MCS)and those two alternatively arranged crystal phases endow T-MCS with excellent bulk phase charge separation performance for the slight energy level difference between ZB-MCS and WZ-MCS.S-scheme carriers transfer route between NiS and T-MCS can accelerate the interfacial charge separation and retain the active electrons and holes,meanwhile,co-catalyst Ni_(2)P as electron receiver and proton reduction center can further optimize the H_(2)evolution reaction kinetics based on the surface Schottky barrier effect.The above-formed homo-heterojunctions can establish multiple charge transfer channels in the bulk phase of T-MCS and interface of T-MCS and Ni_(2)P-NiS.Under the synergistic effect of twinned homojunction,S-scheme heterojunction,and Schottky barrier,the ternary Ni_(2)P-NiS/T-MCS com-posite manifested an H_(2)production rate of 122.5 mmol h^(-1)g^(-1),which was 1.33,1.24,and 2.58 times higher than those of the NiS/T-MCS(92.4 mmol h^(-1)g^(-1)),Ni_(2)P/T-MCS(98.4 mmol h^(-1)g^(-1)),and T-MCS(47.5 mmol h^(-1)g^(-1)),respectively.This work demonstrates a promising strategy to develop efficient sul-fides photocatalyst toward targeted solar-driven H_(2)evolution through homo-heterojunction engineering.

关键词： Photocatalytic H_(2)evolution Twinned Mn_(0.5)Cd_(0.5)S Homojunction S-scheme heterojunction Schottky barrier

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