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Magnetic and magnetocaloric effect in a stuffed honeycomb polycrystalline antiferromagnet GdInO_(3)

Chinese Physics B 2022年第6期31卷 656-662页

作者： Yao-Dong Wu Wei-Wei Duan Qiu-Yue Li Yong-Liang Qin Zhen-Fa Zi Jin Tang Universities Joint Key Laboratory of Photoelectric Detection Science and Technology in Anhui Province Anhui Province Key Laboratory of Simulation and Design for Electronic Information Systemand School of Physics and Materials EngineeringHefei Normal UniversityHefei 230601China Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryHFIPSAnhuiChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

The magnetic and magnetocaloric properties were studied in a stuffed honeycomb polycrystalline antiferromagnet GdInO_(3).The onset temperature of antiferromagnetic ordering was observed at~2.1 *** thermal and magnetic hystereses suggest a reversible magnetocaloric effect(MCE)in the GdInO_(3) *** the magnetic field changes of 0 kOe-50 kOe and 0 kOe-70 kOe,the maximum magnetic entropy change values are 9.65 J/kg·K and 18.37 J/kg·K,respectively,near the liquid helium temperature,with the corresponding relative cooling power values of 115.01 J/kg and211.31 J/*** MCE investigation of the polycrystalline GdInO_(3) serves to illuminate more exotic properties in this frustrated stuffed honeycomb magnetic system.

关键词： GdInO_(3) magnetization magnetocaloric effects stuffed honeycomb antiferromagnet

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Design approach of contingency point return trajectory for manned lunar missions based on homotopy continuation 3

Design approach of contingency point return trajectory for m...

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2024 3rd International Conference on Aerospace, Aerodynamics and Mechatronics Engineering, AAME 2024

作者： Lu, Lin Li, Haiyang Dong, Tianshan Zhu, Binyu College of Aerospace Science and Engineering National University of Defense Technology Changsha410073 China Hunan Key Laboratory of Intelligent Planning and Simulation for Aerospace Missions Changsha410073 China Beijing Institute of Spacecraft System Engineering Beijing100094 China

In terms of the requirement of contingency return during the circumlunar flight phase in manned lunar missions, this article presents a contingency point return trajectory design approach. In consideration of the point return constraint, an initial value estimate model is proposed. A nonlinear programming problem is constructed and solved by adopting an improved differential evolution algorithm with good global search ability. On the basis of the initial value estimate, homotopy continuation is used to gradually approximate and obtain the high-fidelity solution. The simulation results indicate that the design approach can effectively calculate a contingency point return trajectory with good convergence. © Published under licence by IOP Publishing Ltd.

关键词： Lunar missions

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Earlier peak photosynthesis timing potentially escalates global wildfires

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National science Review 2024年第09期11卷 171-180页

作者： Gengke Lai Jialing Li Jun Wang Chaoyang Wu Yongguang Zhang Constantin M.Zohner Josep Pe?uelas Quansheng Ge International Institute for Earth System Sciences Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing University Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural ResourcesSchool of Geography and Ocean Science Nanjing University The Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Huangshan National Park Ecosystem Field Scientific Observation and Research Station of the Ministry of Education Jiangsu International Joint Carbon Neutrality Laboratory Nanjing University Department of Environmental Systems Science Institute of Integrative BiologyETH Zurich CSIC Global Ecology Unit CREAF-CSIC-UAB CREAF Cerdanyola del Vallès

More intense fire weather due to climate change is implicated as a key driver of recent extreme wildfire events. As fuel stock, the role of vegetation and its phenology changes in wildfire dynamics, however is not fully appreciated. Using long-term satellite-based burned areas and photosynthesis observations, we reveal that an earlier peak photosynthesis timing(PPT) potentially acts to escalate subsequent wildfires, with an increase in the global average burned fraction of 0.021%(～2.20 Mha) for every additional day of PPT advancement. Satellite observations and Earth system modeling consistently show that this fire escalation is likely due to intensified drought conditions and increased fuel availability associated with the climate feedback arising from earlier PPT. Current fire-enabled dynamic global vegetation models can reproduce the observed negative correlation between PPT and burned area but underestimate the strength of the relationship notably. Given the continued PPT advancement owing to climate change, the bioclimatic effects of vegetation phenology change suggest a potentially pervasive upward pressure on future wildfires.

关键词： vegetation photosynthesis phenology wildfire climate feedback Earth system model

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Research and Implementation of Model Engineering Environment Integration Based on OpenMBEE 21st

Research and Implementation of Model Engineering Environment...

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21st Asia simulation Conference, AsiaSim 2022

作者： Xue, Junjie Zhou, Junhua Shi, Guoqiang Feng, Chaoqun Xu, Lin Liu, Penghua Quan, Hongyan Engineering Research Center Beijing Simulation Center Beijing100854 China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering Beijing100854 China Science and Technology on Space System Simulation Laboratory Beijing Simulation Center Beijing100854 China Yunnan Chensheng Tendering Consulting Co. Ltd. Kuming650102 China School of Computer Science and Technology East China Normal University Shanghai200062 China

ISBN: (纸本)9789811991974

Aiming at the problem of integrating open tools in a user development environment in complex product design, an integration strategy of model engineering environment based on OpenMBEE is studied. It is based on the technologies of user identity unified authentication and user interaction data collaboration. Specifically, in the solution of unified identity authentication on cross-platform, the extended controller method is provided based on the message queue information flow mechanism. Then, the separation of business logic, data information, and interactive view of user unified authentication are realized, on the basis, that the function of unified identity authentication is realized by using the Software Development Kit (SDK) of OpenMBEE. Besides, in the study of user interaction data collaboration technology, three-layer collaboration mechanisms are proposed, they are the presentation layer collaboration, the business layer collaboration, and the persistence layer collaboration. When the jQuery programming framework is integrated into the bootstrap front-end framework, combing with the OpenMBEE back-end server interface, the collaboration of user interaction data is realized. Through experiments and project practice analysis, the user unified authentication strategy and user interactive collaboration strategy are tested respectively for proving the effectiveness and feasibility of the proposed method. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Authentication

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Dynamic Economic Scheduling with Self-Adaptive Uncertainty in Distribution Network Based on Deep Reinforcement Learning

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Energy Engineering 2024年第6期121卷 1671-1695页

作者： Guanfu Wang Yudie Sun Jinling Li Yu Jiang Chunhui Li Huanan Yu He Wang Shiqiang Li State Grid Liaoning Electric Power Co. Ltd.Liaoyang Power Supply CompanyLiaoyang111000China Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of Education(Northeast Electric Power University)Jilin132012China Jilin Northeast Electric Power University Science and Technology Development Co. Ltd.Jilin132012China

Traditional optimal scheduling methods are limited to accurate physical models and parameter settings, which aredifficult to adapt to the uncertainty of source and load, and there are problems such as the inability to make dynamicdecisions continuously. This paper proposed a dynamic economic scheduling method for distribution networksbased on deep reinforcement learning. Firstly, the economic scheduling model of the new energy distributionnetwork is established considering the action characteristics of micro-gas turbines, and the dynamic schedulingmodel based on deep reinforcement learning is constructed for the new energy distribution network system with ahigh proportion of new energy, and the Markov decision process of the model is defined. Secondly, Second, for thechanging characteristics of source-load uncertainty, agents are trained interactively with the distributed networkin a data-driven manner. Then, through the proximal policy optimization algorithm, agents adaptively learn thescheduling strategy and realize the dynamic scheduling decision of the new energy distribution network ***, the feasibility and superiority of the proposed method are verified by an improved IEEE 33-node simulationsystem.

关键词： Self-adaptive the uncertainty of sources and load deep reinforcement learning dynamic economic scheduling

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A Compact Antenna Test Range Designed by All-Dielectric Transmitarray

A Compact Antenna Test Range Designed by All-Dielectric Tran...

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International Conference on Microwave and Millimeter Wave technology Proceedings

作者： Fan Liu Jing Ma Bin Shi Zhong-bo Zhu Lin Peng The Key Laboratory of Microwave and Optical Wave Application Technology Guilin University of Electronic Technology Guilin Guangxi China The Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China The National Key Laboratory of Science and Technology on Space Microwave Xi'an China

ISBN: (数字)9798350389968

ISBN: (纸本)9798350389975

In this paper, an all-dielectric transmitarray compact antenna test range (TACATR) is proposed. The TACATR can be used as a low-cost alternative to traditional reflector compact antenna test range. The aperture perturbation mechanisms of the TACATR have been investigated, including aperture scattering interference and edge diffraction. Two optimization strategies are proposed to enhance the performance of the quiet zone (QZ). On the one hand, the unwanted edge diffraction is suppressed by employing suitable feeding sources and optimizing the focal aperture ratio (F/D). On the other hand, the interference of aperture scattering in QZ was further suppressed by optimizing the additional phase shift (APS). As an example, a Circular transmitarray (TA) with the dimension of 91mm was designed, which verifies the mechanism of interferences suppressing.

关键词： Microwave antennas Diffraction Horn antennas Perturbation methods Transmitting antennas Millimeter wave technology Scattering

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Ultra-wideband High Gain Circularly Polarized All Dielectric Lens Antenna

Ultra-wideband High Gain Circularly Polarized All Dielectric...

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International Conference on Microwave and Millimeter Wave technology Proceedings

作者： Chen Wang Jing Ma Bin Shi Zhong-bo Zhu Lin Peng The Key Laboratory of Microwave and Optical Wave Application Technology Guilin University of Electronic Technology Guilin Guangxi China The Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China The National Key Laboratory of Science and Technology on Space Microwave Xi'an China

ISBN: (数字)9798350389968

ISBN: (纸本)9798350389975

In this paper, An ultra-wideband high gain circularly polarized all dielectric lens antenna is proposed. The lens antenna consists a linearly polarized horn and a dielectric lens with a gap. The impedance bandwidth, axial ratio and gain of the antenna can be improved by changing the shape of the lens. The PSO-GA is used to improve the design optimization efficiency of lens antenna, and the modeling time is shortened through the integrated modeling technology. The impedance bandwidth of the lens antenna is 40%, the maximum axial ratio is 2.8dB, and the maximum gain is 21.5dBic at 65GHz. In the 60-90GHz frequency band, the gain is greater than 20.5dBic.

关键词： Microwave antennas Polarization Shape Horn antennas simulation Bandwidth Ultra wideband antennas

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Broadband Wide-Angle Linear-to-Circular Polarization Converter Based on Metal Strips Loaded Metasurface

Broadband Wide-Angle Linear-to-Circular Polarization Convert...

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2022 International Applied Computational Electromagnetics Society Symposium, ACES-China 2022

作者： Wang, Jingwen Deng, Shasha Chen, Weidong Zhang, Zhongxiang Chen, Chang University of Science and Technology of China School of Information Science and Technology Hefei230031 China Hefei Normal University Key Laboratory of Simulation and Design for Electronic Information System Hefei230601 China

ISBN: (纸本)9781665452366

A transmissive broadband wide-angle linear-to-circular polarization converter based on metal strips loaded metasurface is proposed in this paper. The converter is composed of three metallic layers separated by dielectric substrates and the metal strips printed on each layer keep orthogonal to each other. To further investigate the operating mechanism of the design, equivalent circuit models are presented. Moreover, the converter is verified to be effective in polarization conversion through the full-wave simulation. With the insertion loss less than 2 dB and 3 dB, the simulation 3-dB axial ratio (AR) bandwidth keeps 67% and 76%, respectively. Furthermore, at an increased incident angle of 40°, the device can still maintain an AR bandwidth over 47% at 2 dB insertion loss, which manifests the validity and rationality of the converter design. © 2022 IEEE.

关键词： Strip metal

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A Band Stop Decoupling Structure for Circularly Polarized Antennas With Different Intervals

A Band Stop Decoupling Structure for Circularly Polarized An...

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2022 International Applied Computational Electromagnetics Society Symposium, ACES-China 2022

作者： Ding, Yuhang Deng, Shasha Chen, Weidong Zhang, Zhongxiang Chen, Chang University of Science and Technology of China School of Information Science and Technology Hefei230031 China Hefei Normal University Key Laboratory of Simulation and Design for Electronic Information System Hefei230601 China

ISBN: (纸本)9781665452366

In this paper, a novel band stop decoupling structure (BSDS) for circularly polarized microstrip antenna array with different intervals to realize mutual coupling reduction is proposed. The BSDS is composed of complementary split-rings resonator (CSRRs) and split-rings resonator (SRRs), where the CSRRs block TM waves by electric resonance and the SRRs block TE waves by magnetic resonance, respectively. The proposed design is verified by the simulation and the results indicate that the isolation enhancement more than 35 dB can be obtained at the center frequency of 3.4 GHz when the center spacing is 0.37 λ0. Futhermore, when the center spacing reduces to 0.26 λ0, the mutual coupling remains below 25 dB. Besides, the BSDS can improve the radiation pattern offset without affecting the gain and the backward radiation of antennas. © 2022 IEEE.

关键词： Magnetic resonance

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Knowledge-driven material design platform based on the whole-process simulation and modeling

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International Journal of Modeling, simulation, and Scientific Computing 2022年第2期13卷 1-15页

作者： Gongzhuang Peng Tie Li Xiang Zhai Wenzheng Liu Heming Zhang National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing 100083 P.R.China Shanghai Electro-Mechanical Engineering Institute Shanghai 201109 P.R.China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering Beijing 100854 P.R.China Beijing Complex Product Advanced Manufacturing Engineering Research Center Beijing Simulation Center Beijing 100854P.R.China Science and Technology on Space System Simulation Laboratory Beijing Simulation Center Beijing 100854P.R.China National CIMS Engineering Research Center Tsinghua University Beijing 100084P.R.China

In order to realize the agility,collaboration and visualization of alloy material devel-opment process,a product development platform based on simulation and modeling technologies is established in this *** this platform,the whole-process simulation module builds multi-level simulation models based on metallurgical mechanisms from the production line level,the thermo-mechanical coupling field level and the microstructure evolution *** design knowledge management module represents the multi-source heterogeneous material design knowledge through ontology model,including customers’requirement knowledge,material component knowledge,process design knowledge and quality inspection knowledge,and utilizes the case-based reasoning approach to reuse the *** data-driven modeling module applies machine learning algorithms to mine the relationships between product mechanical properties,material components,and process parameters from historical samples,and utilizes multi-objective optimiza-tion algorithms to find the optimal combination of process *** of the developed platform in actual steel mills shows that the proposed method helps to improve the efficiency of product design process.

关键词： Product development knowledge-based engineering multi-scale simulation performance prediction model

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