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Optimal Scheduling of Distribution System with Edge Computing and Data-driven Modeling of Demand Response

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 989-999页

作者： Jianpei han Nian Liu Jiaqi shi State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

High penetration of renewable energies enlarge the peak-valley difference of the net load of the distribution system,which puts forward higher requirements for the operation scheduling of the distribution *** the perspective of leveraging demand-side adjustment capabilities,an optimal scheduling method of the distribution system with edge computing and data-driven modeling of price-based demand response(PBDR)is *** introducing the edge computing paradigm,a collaborative interaction framework between the control center and the edge nodes is designed for the optimization of the distribution *** the edge nodes,a classified XGBoost-based PBDR modeling method is proposed for large-scale differentiated *** the control center,a two-stage optimization method integrating pre-scheduling and re-scheduling is proposed based on demand response results from all edge *** the information interaction between the control center and edge nodes,the optimized scheduling of the distribution system with large-scale users is ***,a case study is implemented on the modified IEEE 33-node system,which verifies that the proposed classified modeling method has lower errors,and it is beneficial to improve the economics of the system ***,the simulation results show that the application of edge computing can significantly reduce the calculation time of the optimal scheduling problem with PBDR modeling of large-scale users.

关键词： Demand response distribution system edge computing optimal scheduling XGBoost

Polymer-bubbling for one-step synthesis of three-dimensional cobalt/carbon foams against electromagnetic pollution

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Journal of Materials Science & Technology 2021年第34期93卷 7-16页

作者： Fengyuan Wang ping Xu Ning shi Liru Cui Yahui Wang Dawei Liu Honghong Zhao Xijiang han Yunchen Du MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China

Constructing three-dimensional(3D)foam-like structure in magnetic metal/carbon composites is regarded as a promising pathway to reinforce their electromagnetic(EM)***,a nitrateassisted polymer-bubbling strategy is reported for the synthesis of Co/carbon foams,which is simply accomplished by direct pyrolyzing the mixture of polyvinylpyrrolidone(PVP)and cobalt nitrate hexahydrate(Co(NO_(3))_(2)·6 H_(2) O).Co(NO_(3))_(2)·6H_(2)O not only plays as the source of Co nanoparticles,but also accounts for the formation of 3D microstructure through releasing *** manipulating the weight ratio of Co(NO_(3))_(2)·6H_(2)O to PVP,the chemical composition,microstructure,and EM properties of these composites can be easily *** the weight ratio reaches 1.5,the resultant composite displays good microwave absorption performance,whose reflection loss intensity and effective absorption bandwidth are superior to those of many common Co/C *** analysis reveals that such architecture is greatly helpful to establish cross-linked conductive networks in the wax matrix,resulting in powerful dielectric loss under low absorber ***,3D microstructure is also beneficial for multiple reflections that equal to extend the transmission path of incident EM *** synthesis strategy and desirable properties of these magnetic carbon foams may render them as the low-cost substitute of 3D graphene for the application against EM pollution.

关键词： Polymer-bubbling Three-dimensional foams Co/C composites Electromagnetic pollution Microwave absorption

Quantifying Land Use Change in Zhejiang Coastal Region,China Using Multi-Temporal Landsat TM/ETM+Images

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Pedosphere 2007年第6期17卷 712-720页

作者： DING han WANG Ren-Chao WU Jia-ping ZHOU Bin shi Zhou DING Li-Xia Institute of Agricultural Remote Sensing and Information System Zhejiang University Hangzhou 310029 （China） Zhejiang Institute of Land Survey and Planning Hangzhou 310007 （China）

Landsat Thematic Mapper （TM） and Enhanced Thematic Mapper Plus （ETM＋） images in 1985, 1986, 1993, 1994 and 2001 were used to quantify the land use and land cover changes （LUCC） in the Zhejiang coastal region with a stratified unsupervised classification technique in conjunction with visual interpretation and to attempt an identification of the socioeconomic driving forces. In level I an overall accurate classification was achieved using a modified Anderson＇s Ⅰ/Ⅱ/Ⅲ-level classification scheme. The overall accuracy of the land use classification at Anderson level Ⅰ were 89.7% （1985）, 91.6% （1993）, and 90.4% （2001）. The most rapid land use change was a dramatic increase in urban or built-up areas, which quadrupled from 1985 to 2001. Over 90% of this newly expanded built-up area was originally paddy fields or other croplands. In different parts of the Zhejiang coastal region, urban land expansion was spatially uneven. Temporally, land use development did not stabilized, and the two study periods of time （1985-1993 and 1993-2001） had different transition styles. Socioeconomic factors, such as gross domestic product, total population, and financial expenditure, were all highly correlated with the expansion of urban or built-up areas. Based on the degree of urban sprawl and socioeconomic factors, cities and towns were further divided into six subgroups, which may help decision makers improve land use for the region.

关键词： coastal region driving factors land use change urban sprawl

Dynamic Damage Detection and Assessment on the Bogie Frame of High-Speed Train Based on the Coupled Elastic and Multibody Dynamics Scheme

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Acta Mechanica Solida Sinica 2023年第5期36卷 633-646页

作者： Yating han Wangdong shi Wenjie Feng School of Civil Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Hebei Key Laboratory for Mechanics of Smart Materials and Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

The dynamic cumulative damage of rigid-flexible coupling model of high-speed train with flexible bogie frame is performed by using the coupled scheme of elastic and multibody dynamics *** motion equations of the present problem are firstly established by integrating the finite element method and floating frame of reference approach based on the virtual power principle and D'Alembert *** process of condensing the elastic DOFs of the obtained finite element model involving the incorporation of the substructure technique and sparse approximate inverse method is tentatively carried ***,the motion equations are further solved by virtue of the generalized α method and the Jacobian-free Newton-Krylov *** the superiority of coupled scheme is proven by comparing with the traditional ***,besides the dynamic behaviors of the considered vehicle model,the time-variations of stresses on the elastic bogie frame's dangerous nodes and the distributions of stresses of bogie frame at some specified moments are synchronously calculated and *** importantly,the real-time and time-varying cumulative damages of some typical nodes on bogie frame are investigated.

关键词： Coupled elastic and multibody dynamics scheme Flexible bogie frame Dynamic damage analysis

Features and formulae of sediment incipient motion in vegetated flow environment

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Journal of Hydrodynamics 2024年第2期36卷 331-339页

作者： Yu-xuan Xu Wei-jie Wang shi-bao Zhang han-qing Zhao Xue-kai Chen Hai-ping Zhang School of Water Conservancy North China University of Water Resources and Electric PowerZhengzhou450045China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing100038China China Three Gorges Corporation Wuhan430010China

Aquatic vegetation is a vital component of natural river ecosystems,playing a crucial role in maintaining ecological balance,providing habitat and improving water ***,the presence of vegetation results in increased resistance in vegetated channels compared with non-vegetated channels,rendering traditional sediment movement predictions inadequate for the ***,the concept of a vegetation influence factor,denoted by CDah,has been proposed by previous researchers to represent the effect of vegetation on sediment movement in *** this study,we focus on exploring the vegetation resistance coefficient(CD)among the vegetation influence factors,evaluating two different calculation methods for vegetation resistance coefficient,and presenting two expressions through genetic algorithm analysis to predict the incipient flow velocity of sediment in vegetated *** predicted values from the new formulae show excellent agreement with measured data,highlighting the high accuracy of the proposed methods in predicting the incipient flow velocity of *** results provide a solid theoretical basis for understanding the influence of aquatic vegetation on sediment particle movement.

关键词： Vegetation flow vegetation resistance coefficient genetic algorithm sediment initiation

Topological Vortices in Superfluid Films

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Communications in Theoretical Physics 2005年第1X期44卷 160-164页

作者： WANGJun-ping DUANYi-shi InstituteofTheoreticalPhysics LanzhouUniversityLanzhou730000China InstituteofScienceandTechnologyforOpto-electronicInformation YantaiUniversityYantai264005China

We study the topological structure of the vortex system in a superfiuid film. Explicit expressions for the vortex density and velocity field as functions of the superfluid order parameter are derived. The evolution of... 详细信息

关键词：拓扑旋涡超流体拓扑结构旋涡密度

Microstructure and Elevated Temperature Tensile Behavior of Directionally Solidified Ni-rich NiAl-Mo(Hf) Alloy

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Journal of Materials Science & Technology 2011年第5期27卷 437-442页

作者： ping han Yihui Qi Jianting Guo Department of Physics Bohai University Jinzhou 121013 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The microstructure, high strain rate superplasticity and tensile creep behavior of directionally solidified （DS） NiAI-Mo（Hf） alloy have been investigated. The alloy exhibits dendritic structure, where dendritic arm is NiAI phase, interdendritic region is Ni3AI phase, and Mo-rich phase distributes in the NiAI and Ni3AI phases. The alloy exhibits high strain rate superplastic deformation behavior, and the maximum elongation is 104.2% at 1373 K and strain rate of 1.04xi0-2 s-I. The balance between strain hardening （by dislocation glide） and strain softening （by dynamic recovery and recrystallization） is responsible for the superplastic deformation. All the creep curves of the DS NiAI-Mo（Hf） alloy have similar shape of a short primary creep and dominant steady creep stages, and the creep strain is great. The possible creep deformation mechanism was also discussed. The creep fracture data follow the Monkman-Grant relationship.

关键词： NiA1 alloy Directional solidification Superplasticity Creep

Embedding ensemble tracking in a stochastic framework for robust object tracking

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1476-1482页

作者： Yu GU ping LI Bo han Institute of Industrial Process Control Zhejiang University Hangzhou 310027 China

We propose an algorithm of embedding ensemble tracking in a stochastic framework to achieve robust tracking performance under partial occlusion,illumination changes,and abrupt *** operates on likelihood images generated by the ensemble method,and combines mean shift and particle filtering in a principled way,where a better proposal distribution is de-signed by first propagating particles via a motion model,and then running mean shift to move towards their local peaks in the likelihood *** observation model in the particle filter incorporates global and local information within a region,and an adaptive motion model is adopted to depict the evolution of the object *** algorithm needs fewer particles to manage the tracking task compared with the general particle filter,and recaptures the object quickly after occlusion *** on two image sequences demonstrate the effectiveness and robustness of the proposed algorithm.

关键词： Ensemble tracking Particle filter Mean shift Likelihood mean

Numerical investigation of the influence of vortex generator on propeller cavitation and hull pressure fluctuation by DDES

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Journal of Hydrodynamics 2022年第3期34卷 444-450页

作者： Yun Long han-qiao han Bin Ji Xin-ping Long Wuhan Second ship Design and Research Institute Wuhan430064China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan430072China

In this study,the delayed detached eddy simulation(DDES)is coupled with a homogenous cavitation model to simulate the cavitating turbulent flow around a propeller behind a full body ship with special emphasis on the influence of the vortex generator(VG)on the propeller cavitation and the hull pressure *** small calculation uncertainty as evaluated by the DDES verification and validation(V&V)method indicates that the present simulation can accurately reproduce the propeller performance and cavitation,and the predicted hull pressure fluctuation is in a fairly good agreement with the available experimental *** mechanism is explored through the current numerical results how the VG affects the local velocity distribution,along with the influences of the VG on the propeller cavitation and the hull pressure *** is shown that the streamwise vortex is induced by the VG near the hull boundary *** very low velocity region in the hull wake is reduced due to the effect of the streamwise ***,the propeller cavitation develops more mildly and the hull pressure fluctuation decreases due to the influence of the VG.

关键词： Propeller cavitation delayed detached eddy simulation(DDES) vortex generator(VG) streamwise vortex