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Dynamic Equivalent Modeling for Black-box Microgrids Under Multi-operating-point by Using LSTM

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 639-648页

作者： Yunlu Li Josep M.Guerrero junyou Yang Yajuan Guan Guiqing Ma Jiawei Feng School of Electrical Engineering Shenyang University of TechnologyShenyang 110819China Department of Energy Technology Center for Research on Microgrids(CROM)Aalborg University9220 Aalborg EastDenmark

Since the high penetration of distributed energy sources complicates the dynamics of electrical power systems,accurate dynamic models are indispensable for study on the transient behavior of the microgrid(MG).In some practices,the lack of full detailed information results in failure of dif-ferential equation based dynamic modeling,which leads to a demand for a black-box MG modeling *** is a critical challenge to maintain the effectiveness of the black-box model under a wide operating range and various fault *** this paper,inspired by the mathematical equivalence between the recurrent neural network(RNN)and differential-algebraic equations(DAEs),a dynamic equivalent modeling method,using long short-term memory(LSTM),is presented to tackle this *** first,the modeling equivalence and advantages of our basic idea are ***,modeling procedures,including data preparation and design guidelines,are ***,the proposed method is applied to a multi-microgrid testing system for performance *** results,under various scenarios,reveal that the proposed modeling method has an adequate capability for representing the dynamic behaviors of a black-box MG under grid fault and operating point changing *** Terms-Deep learning,dynamic behavior,dynamic equivalent model,microgrid,neural network.

关键词： Deep learning dynamic behavior dynamic equivalent model microgrid neural network

On the characterization of microstructure and fracture in a high-pressure die-casting Al-10 wt%Si alloy

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Progress in Natural Science:Materials International 2020年第2期30卷 221-228页

作者： Xiangyi Jiao Chaofeng Liu Jun wang Zhipeng Guo junyou wang Zhuoming wang Junming Gao Shoumei Xiong School of Materials Science and Engineering Tsinghua University Key Laboratory for Advanced Materials Processing Technology Tsinghua University Hong Bang Die Casting (NanTong) CO. LTD

Microstructure and fracture behavior in a high-pressure die-casting Al-10 wt%Si alloy have been investigated using optical microscope(OM),scanning electron microscope(SEM) and a high-resolution laboratory computed tomography(CT).The results showed that a typical heterogeneous microstructure of the alloy comprised α-Al rich region,eutectic silicon band region and *** microstructure patterns highly dependent on fluid convection and rapid *** high filling speed,externally solidified crystals(ESCs) and the growing dendrites migrated in center and formed α-Al rich *** particles was discharged and enriched in the final solidified liquid,forming eutectic silicon *** Si particles and brittle Fe-rich phases served as obstacles prevented dislocation migration,causing local stress *** to large movable slip systems in α-Al rich region,the propagation path of the crack was greatly ***-shrinkage that induced by dense impinging dendrites led to the microcracks along the boundary of dendrites which promoted intergranular fracture.

关键词： Fracture Hypoeutectic Al-10Si Microstructure heterogeneity High-pressure die-casting

A large-sized basal ankylopollexian from East Asia, shedding light on early biogeographic history of Iguanodontia

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Science Bulletin 2018年第9期63卷 556-563页

作者： Xing Xu Qingwei Tan Yilong Gao Zhiqiang Bao Zhigang Yin Bin Guo junyou wang Lin Tan Yuguang Zhang Hai Xing Key Laboratory of Evolutionary Systernatics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Long Hao Institute of Geology and Paleontology Hohhot 010010 China Bureau of Land and Resources of Bayannur Bayannur 015000 China Inner Mongolia Museum of Natural History Hohhot 010020 China Beijing Museum of Natural History Beijing Academy of Science and Technology Beijing 100050 China

A presumably mostly quadrupedal ankylopollexian iguanodontian, Bayannurosaurus perfectus gen. et ***., is reported here, and is represented by an excellently well-preserved skeleton from the Lower Cretaceous Bayingebi Formation of Inner Mongolia, China. The diagnosis of the taxon includes several autapomorphies, notably a dorsally directed, strap-like posterodorsal process of the jugal and a horizontally oriented preacetabular process of the ilium. The nearly complete caudal series retains eight posterior-most caudals with procoelous, trapezoidal centra in dorsal view, and the last three caudals are fully fused. The discovery of B. perfectus opens a critical new window on the early evolution and intercontinental dispersal of Iguanodontia. The skeleton displays a transitional morphology between nonhadrosauriform ankylopollexians and Hadrosauriformes. A phylogenetic analysis indicates that Bayannurosaurus is positioned higher on the tree than Hypselospinus, but below Ouranosaurus just outside of Hadrosauriformes. The tree topology of Iguanodontia with temporal and spatial constraints reveals a possible biogeographic scenario supported by the statistical dispersal-vicariance analysis: around the J/K boundary, non-hadrosauriform ankylopollexians experienced multiple dispersal events from Europe to Asia, accompanying the coeval fall of the global sea level.

关键词：大尺寸基础东亚历史水平地面种系发生 nov 白垩纪

Efficient and Generic Preparation of Diverse Polyelectrolyte Nanogels by Electrostatic Assembly Directed Polymerization

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CCS Chemistry 2020年第6期2卷 1016-1025页

作者： Peng Ding Jianan Huang Cheng Wei Wei Liu Wenjuan Zhou Jiahua wang Mingwei wang Xuhong Guo Martien A.Cohen Stuart junyou wang State Key Laboratory of Chemical Engineering and Shanghai Key Laboratory of Multiphase Materials Chemical EngineeringEast China University of Science and TechnologyShanghai 200237

Nanogels hold promise as soft and functional carriers and nanoreactors,but whether they will ever reach the stage of large-scale application depends crucially on efficient production methods,and on what interesting properties and functionalities they can *** particular,nanogels consisting of highly charged polyelectrolyte have not yet been very much ***,the authors present a novel and generic strategy for controlled and efficient synthesis of a large diversity of polyelectrolyte *** method is based on polymerizing an ionic monomer in the presence of an oppositely charged polyion-neutral diblock copolymer as template,while adding a *** growing polymer chains assemble with the template,forming polyion complex micelles,which dissociate upon increasing salt *** separation yields nanogels with well-controlled size and properties,and free template polymers that can be used *** design can be applied generally to a wide range of both cationic and anionic monomers,as well as various ***-up production presents no problems as increasing monomer concentration(hundreds of mM)and reaction volume(up to 1 L)hardly compromise product ***,the obtained nanogels with their well-controlled size,morphology,chemistry,and cross-linking degree perform well as soft nanocarriers and catalytic nanoreactors.

关键词： nanogel polyelectrolyte electrostatic interaction template polymerization scale-up production soft nanocarrier nanoreactor

基于随机森林的电容式土壤水分传感器校准研究

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地质科技通报 2023年第5期42卷 249-256页

作者：汪正胡顺马瑞孙自永葛孟琰王俊友乔树锋中国地质大学(武汉)环境学院武汉430078

土壤含水量信息对于自然生态修复、农田灌溉管理、土体工程建设等具有重要的意义,电容式土壤水分传感器是获取该信息的主要途径之一。为准确校准电容式土壤水分传感器(以5TE设备为例)的土壤含水量观测数据,开展了不同温度、含盐量、土... 详细信息

土壤含水量信息对于自然生态修复、农田灌溉管理、土体工程建设等具有重要的意义,电容式土壤水分传感器是获取该信息的主要途径之一。为准确校准电容式土壤水分传感器(以5TE设备为例)的土壤含水量观测数据,开展了不同温度、含盐量、土壤含水量条件下的土壤介电常数、电导率和温度观测实验,构建了基于随机森林机器学习方法的土壤含水量估计模型。结果表明:①变温、变含盐量情况下,土壤介电常数受含盐量和温度影响显著,仅基于土壤介电常数的传统土壤含水量估计模型失效;②以电容式土壤水分传感器观测的土壤介电常数、电导率和温度数据为输入,基于随机森林机器学习方法的土壤含水量估计模型可有效改善土壤含水量估计结果(RMSE为0.05 m^(3)/m^(3),R^(2)为0.77;修正Topp公式的土壤含水量估计结果:RMSE为0.07 m^(3)/m^(3),R^(2)为0.54);③土壤电导率观测对土壤含水量估计最为重要,介电常数次之,温度最弱,但均未达到可忽略不计的程度。研究成果可为电容式土壤水分传感器在变温、变含盐量地区的成功应用提供支撑。

关键词：土壤含水量介电常数电导率温度随机森林土壤水分传感器

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压铸铝合金变速箱体参数的有限元分析

特种铸造及有色合金 2022年第4期42卷 521-525页

作者：魏言标卢润泽王俊有黄明宇南通大学机械工程学院江苏南通226001 雄邦压铸(南通)有限公司开发部江苏文灿压铸有限公司开发部

利用ProCAST有限元分析软件并采用带压室的流态分析对压铸铝合金变速箱体压铸参数进行可视化调节,更能接近实际生产环境。在软件中进行不同参数试验,得出最佳低压速度为0.2 m/s、高速切换点为630 mm、高压速度为5 m/s。将这些参数在3200... 详细信息

利用ProCAST有限元分析软件并采用带压室的流态分析对压铸铝合金变速箱体压铸参数进行可视化调节,更能接近实际生产环境。在软件中进行不同参数试验,得出最佳低压速度为0.2 m/s、高速切换点为630 mm、高压速度为5 m/s。将这些参数在32000 kN布勒压铸机进行试验验证,发现压铸出的变速箱体铸件外观品质良好,没有冷隔、气孔等缺陷,用X射线进行探伤,铸件内部没有观察到缩松、缩孔等缺陷。

关键词：铝合金仿真分析压铸工艺参数优化

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

基于非侵入式负荷分解的家庭负荷两阶段超短期负荷预测模型

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电工技术学报 2024年第11期39卷 3379-3391页

作者：李延珍王海鑫杨子豪陈哲杨俊友沈阳工业大学电气工程学院沈阳110870 丹麦奥尔堡大学能源技术系奥尔堡DK-9220

精细化负荷预测为制定家庭新型需求响应策略或能效管理模式提供了可靠的指导信息与理论基础,而负荷监测系统的广泛研究与发展为家庭设备层的负荷预测提供了有力的数据支撑。基于家庭负荷智能电能表集中数据,该文提出一种集分解-预测一... 详细信息

精细化负荷预测为制定家庭新型需求响应策略或能效管理模式提供了可靠的指导信息与理论基础,而负荷监测系统的广泛研究与发展为家庭设备层的负荷预测提供了有力的数据支撑。基于家庭负荷智能电能表集中数据,该文提出一种集分解-预测一体化的家庭负荷两阶段超短期负荷预测方法。该方法第一阶段提出了基于卷积神经网络(CNN)和双向门控单元(BiGRU)神经网络的非侵入式负荷分解(NILM)模型,解决了目前深度分解模型中特征提取不充分、分解精度低等问题。第二阶段构建了基于时间模式注意力机制(TPA)的时间卷积神经网络(TCN)负荷预测模型,深度挖掘NILM分解数据、集中负荷数据及日期特征等输入变量的深层交互信息,实现家庭设备层的负荷预测。算例部分通过UK-DALE数据集对所提方法进行验证,结果表明,该方法能够获得较高的分解精度和预测效果,为家庭负荷预测提供了良好的条件。

关键词：非侵入式负荷分解负荷预测卷积神经网络双向门控单元神经网络时间卷积网络注意力机制

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory