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Future climate change decreases multi-pathway but increases respiratory human health risks of PAHs across China

National Science Open 2024年第2期3卷 128-147页

作者： Jiaao Bao Xinghui Xia Ying Zhu Bingxiang Zhao Erxue Gu Yanan Liu Xiao Yun Zhenrui Zhang Nannan Xi Yong Geng Ying Xu Zhifeng Yang Derek C.G.Muir Key Laboratory of Water and Sediment Sciences of Ministry of Education State Key Laboratory of Water Environment SimulationSchool of EnvironmentBeijing Normal UniversityBeijing 100875China State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants School of Environmental Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China College of Urban and Environmental Sciences Laboratory for Earth Surface ProcessesSino-French Institute for Earth System SciencePeking UniversityBeijing 100871China National Climate Center China Meteorological AdministrationBeijing 100081China Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education Institute of Environmental and Ecological EngineeringGuangdong University of TechnologyGuangzhou 510006China Aquatic Contaminants Research Division Environment and Climate Change CanadaBurlington L7S 1A1Canada

Future climate change will affect the environmental fate of hydrophobic organic contaminants(HOCs)and associated human health risks,yet the extent of these effects remains ***,we couple a high-resolution environmental multimedia model with a bioaccumulation model to study the multimedia distribution of 16 priority polycyclic aromatic hydrocarbons(PAHs),a group of HOCs,and assess future PAH-related human health risks under varying climate change scenarios over China at a continental *** removing the effects of PAH emission changes,we find that the total PAH concentrations would decrease in the air,freshwater,sediment,soil,and organisms,while the high-molecular-weight PAH would increase in the air with climate warming from 1.5°C to 4°***,the multi-pathway exposure human health risks predominately influenced by dietary ingestion are expected to decrease by 1.7%–20.5%,while the respiratory risks are projected to rise by 0.2%–5.8%in the ***,the persistently high multi-pathway human health risks underscore the need for reducing future PAH emissions by 69%compared with 2009 levels in *** study demonstrates the urgency of limiting PAH emissions under future climate change for public health and highlights the importance of including the contribution of dietary ingestion in human health risk assessment.

关键词： polycyclic aromatic hydrocarbons future climate change human health risks emission reduction

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MTL-JER: Meta-Transfer Learning for Low-Resource Joint Entity and Relation Extraction

MTL-JER: Meta-Transfer Learning for Low-Resource Joint Entit...

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Neural Networks, Information and Communication engineering (NNICE), International Conference on

作者： Da Peng Zhongmin Pei Delin Mo Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China Institute of War Studies Academy of Military Sciences

Joint entity and relation extraction has achieved impressive advances in NLP, such as document understanding and knowledge graph construction. The typical methods for entity and relation extraction typically break down the joint task into several smaller components or stages for ease of implementation, but this leads to a loss of the interconnected knowledge in the triple. Hence, we propose to model the triple in one module jointly. Furthermore, the labeling of a joint entity and relation extraction tasks is costly and domain-specific; therefore, it is important to improve its performance on low-resource data and domain adaption. To address this issue, we suggest using two sources that are rich in information, namely pre-trained models on large data and multi-domain text corpora. Pretraining allows us to provide the model with the fundamental ability to perform joint entity and relationship extraction. Second, through meta-learning on multi-domain text, we can improve the model's generalization capabilities, enabling it to perform well even with limited data. We present MTL-JER, a Meta-Transfer Learning method for Joint Entity and Relation Extraction in low-resource settings in this paper. Using exhaustive experiments on five datasets, we prove that our model obtains optimal results.

关键词： Adaptation models Training data Knowledge graphs Artificial neural networks Data models Data mining Labeling

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Biochar technology cannot offset land carbon emissions in Guangdong province, China

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Carbon Research 2024年第1期3卷 1-14页

作者： Wang, Funing Zhou, Wenneng Wang, Xili Zhao, Qing Han, Mengjie State Key Lab of Clean Energy Utilization Institute of Carbon Neutrality State Environmental Protection Engineering Center for Coal-Fired Air Pollution Control Zhejiang University Hangzhou310027 China Jiaxing Research Institute Zhejiang University Jiaxing314000 China Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds School of Ecology Environment and Resources Guangdong University of Technology Guangzhou510006 China Economic & amp Information center Zhejiang310006 China Department of Earth System Science Ministry of Education Key Laboratory for Earth System Modeling Institute for Global Change Studies Tsinghua University Beijing100084 China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management Institute of Eco-environmental and Soil Sciences Guangdong Academy of Sciences Guangzhou510650 China National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangzhou510650 China

As a highly developed region, Guangdong province has substantial industrial emissions. Its subtropical monsoon climate, characterized by abundant hydrothermal conditions, contributes to a substantial biomass potential. The adoption of potential biomass-based carbon dioxide removal (CDR) technologies, such as biochar, presents an opportunity to mitigate emissions and work towards carbon neutrality in the future. However, the current state of the land carbon balance and the CDR potential of biochar in Guangdong province remains unclear. We first calculated the land carbon balance based on inventory data. Then we estimated the CDR potential of biochar derived from agricultural residues, forestry residues, and bioenergy crops cultivated on marginal lands in Guangdong province using life cycle analysis (LCA). Results show that Guangdong province has not yet achieved carbon neutrality, with a net emission (carbon emissions remaining after offsetting by carbon sinks) of 925.63 Tg CO2e (CO2 equivalent, 1Tg = 106 t) in 2021. Emissions from energy consumption account for the highest proportion, contributing 83.8% of total emissions. In the highest biomass utilization scenario, the maximum CDR potential of biochar derived from all biomass types reaches 84.30 Tg CO2e yr-1, which could offset 9.11% of net carbon emissions in Guangdong province. Our findings provide crucial guidance for setting emission reduction targets and implementing effective mitigation strategies in Guangdong province under temperature warming. Graphical Abstract: (Figure presented.) © The Author(s) 2024.

关键词： Carbon capture and utilization

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Numerical investigation of the critical heat flux in a 5 × 5 rod bundle with multi-grid

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Nuclear engineering and Technology 2022年第5期54卷 1914-1928页

作者： Liu, Wei Shang, Zemin Yang, Shihao Yang, Lixin Tian, Zihao Liu, Yu Chen, Xi Peng, Qian State Key Laboratory of Reactor System Design Technology Nuclear Power Institute of China Chengdu 610213 China School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing 100044 China

To improve the heat transfer efficiency of the reactor fuel assembly, it is necessary to accurately calculate the two-phase flow boiling characteristics and the critical heat flux (CHF) in the fuel assembly. In this paper, a Eulerian two-fluid model combined with the extended wall boiling model was used to numerically simulate the 5 × 5 fuel rod bundle with spacer grids (four sets of mixing vane grids and four sets of simple support grids without mixing vanes). We calculated and analyzed 11 experimental conditions under different pressure, inlet temperature, and mass flux. After comparing the CHF and the location of departure from the nucleate boiling obtained by the numerical simulation with the experimental results, we confirmed the reliability of computational fluid dynamic analysis for the prediction of the CHF of the rod bundle and the boiling characteristics of the two-phase flow. Subsequently, we analyzed the influence of the spacer grid and mixing vanes on the void fraction, liquid temperature, and secondary flow distribution. The research in this article provides theoretical support for the design of fuel assemblies. © 2021 Korean Nuclear Society

关键词： 5 × 5 rod bundle Critical heat flux Eulerian two-fluid model Flow boiling

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Adaptive Adjustment Method for Grid-forming Energy Storage Parameters Based on Buffer Functions and Damping Switching

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Dianli Xitong Zidonghua/Automation of Electric Power systems 2025年第10期49卷 77-86页

作者： Cui, Yang Ma, Boyu Dai, Hanyang Ma, Xin Zhao, Yuting Key Laboratory of Modern Power System Simulation and Control & Renewable Energy Technology Ministry of Education Northeast Electric Power University Jilin132012 China China Electric Power Research Institute Beijing100192 China Electric Power Research Institute of State Grid Ningxia Electric Power Ltd. Co. Yinchuan750002 China

In the development tendency of high penetration of renewable energy and power electronic devices in new power systems, the grid-forming control technology for renewable energy integration mitigates the system stability issues caused by insufficient inertia and damping. However, it also reduces the dynamic regulation performance of the system. This paper proposes an adaptive adjustment method for grid-forming energy storage parameters based on buffer functions and steady-state/transient-state damping switching, to improve the dynamic regulation performance of the system. Firstly, the buffer functions are used in inertia adjustment to enhance the regulation smoothness of the system. Secondly, a steady-state/transient-state damping switching link is introduced in the damping adjustment to reduce the steady-state error of active power output during the frequency reduction process. Thirdly, the fuzzy control is employed to introduce correction terms for inertia and damping, and the stability of the proposed method is analyzed. Finally, simulations validate the effectiveness of the proposed method in enhancing small-signal stability and power response dynamic performance of the system. © 2025 Automation of Electric Power systems Press. All rights reserved.

关键词： Electric power transmission networks

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Design of a Flexible Capture Mechanism Inspired by Sea Anemone for Non-cooperative Targets

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Chinese Journal of Mechanical engineering 2021年第4期34卷 236-248页

作者： Jiankun Yang Chengwei Ren Chenghao Yang Youyu Wang Shumin Wan Rongjie Kang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300350China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110169China Beijing Institute of Spacecraft System Engineering CAST Beijing 100094China

Robotic grippers have been used in industry as end-effectors but are usually limited to operations in pre-defined ***,few devices can capture irregularly shaped dynamic targets in space,underwater and other unstructured *** this paper,a novel continuum arm group mechanism inspired by the morphology and motions of sea anemones is *** is able to dissipate and absorb the kinetic energy of a fast moving target in omni-direction and utilize multiple arms to wrap and lock the target without accurate positioning ***-driven actuation systems are implemented in the individual continuum arms,achieving both bending motion and stiffness *** finite element method,the influence of different configurations of the continuum arm group on the capture performance is analyzed.A robotic prototype is constructed and tested,showing the presented arm group mechanism has high adaptability to capture targets with different sizes,shapes,and incident angles.

关键词： Non-cooperative targets Continuum arm group Wire-driven mechanism

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Research on Leakage Inductance and Eddy Current Loss of Nanocrystalline High-Frequency Transformers 26

Research on Leakage Inductance and Eddy Current Loss of Nano...

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26th International Conference on Electrical Machines and systems, ICEMS 2023

作者： Liu, Yang Liu, Xue Yin, Zhenhuan Dong, Kan Cui, Dongdong Ma, Chi State Key Laboratory for Traction and Control System of EMU and Locomotive China Academy of Railway Science Corporation Limited Beijing China Key Laboratory of Power Electronics and Electric Drive Institute of Electrical Engineering Chinese Academy of Sciences China University of Chinese Academy of Sciences School of Electronic Electrical and Communication Engineering Beijing China

ISBN: (纸本)9798350317589

High-frequency transformers are a vital component of isolated DC/DC converters, and its leakage inductance can be adjusted by changing the winding method of the two-phase windings. Nanocrystalline magnetic cores have been widely applied due to their advantages in high-saturation flux and high magnetic permeability. However, their quite high electrical conductivity can easily lead to appreciable eddy current loss. This paper investigates the mechanism behind the eddy current loss caused by leakage flux by varying the number of windings cross turns, and verifies through simulation that the eddy current loss of nanocrystalline high-frequency transformers increases with increasing leakage inductance. © 2023 IEEE.

关键词： Inductance

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Forming Circle Formations of Multi-agent systems Under Actuator Faults 5th

Forming Circle Formations of Multi-agent Systems Under Actu...

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5th Chinese Conference on Swarm Intelligence and Cooperative Control, CCSICC 2021

作者： Liu, Jiajun Ru, Xinfeng Xia, Weiguo Wang, Chen China National Aeronautical Radio Electronic Research Institute and National Key Laboratory of Science and Technology on Avionics System Integration Shanghai China Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education and School of Control Science and Engineering Dalian University of Technology Dalian China National Engineering Research Center of Software Engineering and the State Key Laboratory of Turbulence and Complex Systems Intelligent Biomimetic Design Lab College of Engineering Peking University Beijing China

ISBN: (纸本)9789811939976

A distributed fault-tolerant formation control law is designed in this paper for multi-agent systems under external disturbances and actuator faults including time-varying loss of effectiveness faults. The initial position of each agent is already on a circle and the control purpose is to form a desired formation on this circle. Based on this local information, a distributed adaptive formation control law is designed by employing the congelation of variables method to deal with time-varying actuator faults. Finally, a simulation example is given to verify the effectiveness of the adaptive fault-tolerant control design method. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Multi agent systems

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Air-Ground Collaborative Mobile Edge Computing:Architecture,Challenges,and Opportunities

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China Communications 2024年第5期21卷 1-16页

作者： Qin Zhen He Shoushuai Wang Hai Qu Yuben Dai Haipeng Xiong Fei Wei Zhenhua Li Hailong College of Communications Engineering Army Engineering University of PLANanjing 210000China Department of Information and Communication Noncommissioned Officer Academy of PAPHangzhou 310000China Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space Ministry of Industry and Information TechnologyNanjing 211106China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China State Key Laboratory for Novel Software Technology Nanjing UniversityNanjing 210023China CMC Political and Law Commission Beijing100120China Xi’an Research Institute of High Technology Xi’an 710025China

By pushing computation,cache,and network control to the edge,mobile edge computing(MEC)is expected to play a leading role in fifth generation(5G)and future sixth generation(6G).Nevertheless,facing ubiquitous fast-growing computational demands,it is impossible for a single MEC paradigm to effectively support high-quality intelligent services at end user equipments(UEs).To address this issue,we propose an air-ground collaborative MEC(AGCMEC)architecture in this *** proposed AGCMEC integrates all potentially available MEC servers within air and ground in the envisioned 6G,by a variety of collaborative ways to provide computation services at their best for ***,we introduce the AGC-MEC architecture and elaborate three typical use ***,we discuss four main challenges in the AGC-MEC as well as their potential ***,we conduct a case study of collaborative service placement for AGC-MEC to validate the effectiveness of the proposed collaborative service placement ***,we highlight several potential research directions of the AGC-MEC.

关键词： air-ground architecture collaborative mobile edge computing

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考虑跨服务模式的网约车派单优化

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Journal of Central South University 2023年第2期30卷 642-653页

作者：王印权吴建军孙会君张宇丰吕莹 State Key Laboratory of Rail Traffic Control and Safety(Beijing Jiaotong University) Beijing 100044China Key Laboratory of Transport Industry of Big Data Application Technologies for Comprehensive Transport of Ministry of Transport(Beijing Jiaotong University) Beijing 100044China Institute of Transportation System Science and Engineering Beijing Jiaotong UniversityBeijing 100044China

为解决多服务模式的网约车市场中所存在的模式间供需时空不匹配的问题,打破模式间派单壁垒,减少车辆无效巡游,提升乘客体验,提出一种基于强化学习的跨模式派单算法。首先,设计跨模式派单的运行规则和相应的仿真环境为算法的训练提供环... 详细信息

为解决多服务模式的网约车市场中所存在的模式间供需时空不匹配的问题,打破模式间派单壁垒,减少车辆无效巡游,提升乘客体验,提出一种基于强化学习的跨模式派单算法。首先,设计跨模式派单的运行规则和相应的仿真环境为算法的训练提供环境支持。其次,针对派单过程中乘客需求动态变化的特点,设计两阶段派单流程。在第一阶段,根据车辆与需求的时空特征确定虚拟派单请求;在第二阶段,采用k最近邻算法对可行派单请求进行细化,选择与虚拟派单请求最为相似的请求作为最终的派单方案。实验表明,与基线方法相比,所提出的跨模式派单算法提升了基础服务模式中3.1%的请求响应率,同时减少了高级服务模式中车辆的空驶时间,实现了更高的经济效益与服务水平。

关键词：网约出行多服务模式跨模式派单强化学习新兴交通系统

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