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Optimal Coordination of Transportable Power Sources and repair Crews for Service restoration of Distribution Networks Considering Uncertainty of Traffic Congestion

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Journal of modern Power Systems and Clean Energy 2024年第1期12卷 189-201页

作者： Zhao Shi yan Xu Dunjian Xie Shiwei Xie Amer m.Y.m.Ghias Nanyang Technological University Singapore the School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(rCs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and rCs is proposed,where the TPSs serve as emergency power supply sources,and the rCs are used to repair the faulted *** the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and *** efficiently solve the proposed stochastic mixed-integer linear program(mILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient *** effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.

关键词： Service restoration distribution network traffic uncertainty transportable power source repair crew stochastic program

A Survey on model Predictive Control of DFIGs in Wind Energy Conversion Systems

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1085-1104页

作者： Shuo yan Junyu Chen minghao Wang Yongheng yang Jose m.rodriguez STEm College RMIT UniversityMelbourneAustralia Hong Kong Polytechnic University Hong KongChina State Key Laboratory of Internet of Things for Smart City(Um) Department of Electrical and Computer EngineeringUniversity of MacaoMacaoChina College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Universidad San Sebastin Campus BellavistaSantiago de ChileCLSantiago de Chile 000000Chile IEEE

This paper presents a comprehensive study on the model predictive control(mPC)of doubly fed induction generators(DFIG)in wind energy conversion systems(WECS);in particular the mPC of the rotor side *** general principle of prevalent mPC strategies is discussed to introduce the theoretical framework in the first ***,mainstream and high-performance mPC methods of DFIGs have been identified as model predictive current control(mPCC),model predictive torque control(mPTC),and model predictive power control(mPPC).Starting from analyzing dynamic models,these mPC strategies are investigated in terms of operating principles and technical *** paper further investigates implementation of mPC strategies in unbalanced *** on the quantitative and qualitative analysis of several case studies,performance of various mPC schemes is compared and their special features are *** for designing mPC strategies of DFIGs in WECS are provided.

关键词： Doubly fed induction generator(DFIG) model predictive control(mPC) wind energy

An Integral method for Solving Dynamic Equations with Fluid–Solid Coupling

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Acta mechanica Solida Sinica 2024年第1期37卷 99-108页

作者： Xin Zhang Jie Liu Pu Xue Shuowen yan Yahao Xu m.S.Zahran School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Civil Engineering Military Technical CollegeCairo 11435Egypt

In this work,a new methodology is presented to mainly solve the fluid–solid interaction(FSI)*** methodology combines the advantages of the Newmark precise integral method(NPIm)and the dual neural network(DNN)*** NPIm is employed to modify the exponential matrix and loading vector based on the DNN integral *** involves incorporating the basic assumption of the Newmark-βmethod into the dynamic equation and eliminating the acceleration term from the dynamic equilibrium *** a result,the equation is reduced to a first-order linear equation ***,the PIm is applied to integrate the system step by step within the *** DNN method is adopted to solve the inhomogeneous term through fitting the integrand and the original function with a pair of neural networks,and the integral term is solved using the Newton–Leibniz *** examples demonstrate that the proposed methodology significantly improves computing efficiency and provides sufficient precision compared to the DNN *** is particularly evident when analyzing large-scale structures under blast loading conditions.

关键词： Newmark precise integral method(NPIm) Dual neural networks(DNN) Fluid-solid interaction(FSI) Dynamic time-history analysis Blast loading

Theoretical screening of cooperative N-bridged dual-atom sites for efficient electrocatalytic nitrogen reduction with remolding insight

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Nano research 2024年第4期17卷 3413-3422页

作者： Huimei Chen yan yang Chi Jiao Zhiwen Zhuo Junjie mao yan Liu Key Laboratory of Functional molecular Solids Ministry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China

The electrocatalytic nitrogen reduction reaction(e-Nrr)is a promising alternative method for the Haber–Bosch ***,it still faces many challenges in searching for high activity,stability,and selectivity catalysts and ascertaining the catalytic mechanism with complete ***,a series of graphene-based N-bridged dual-atom catalysts(m1-N-m2/NC)are systematically investigated via first-principle calculation and a high-throughput screening *** result unveils that N_(2) adsorption on m1-N-m2/NC in bridge-on adsorption mode can effectively break the scaling relationship on single-atom catalysts(SACs).moreover,V-N-ru/NC and V-N-Os/NC are systematically screened out as promising e-Nrr catalysts,with extremely low limiting potentials of-0.20 and-0.18 V,***,the adsorption site competition between*N_(2) and*H,as well as the competitive twin reactions of hydrogen evolution reaction(HEr)on intermediates(N_(n)H_(m))during the e-Nrr process,is systematically evaluated to form a remodeling insight for the reactions in mechanism,and the e-Nrr of new proposed dual-atom catalysts(DACs)is strategically optimized for its high-efficiency performance potential via our remolding insight in e-Nrr *** work provides new ideas and insights for the design and mechanism of e-Nrr catalysts and an effective strategy for rapidly screening highly efficient e-Nrr catalysts.

关键词： nitrogen reduction dual-atom catalysts high-throughput screening hydrogen evolution reaction density functional theory calculations

Numerical Simulation of rainfall-induced Xianchi reservoir Landslide in Yunyang,Chongqing,China

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 505-517页

作者： yan Jinkai mA yan LIU Lei WANG Zhihui rEN Tianxiang Chinese Academy of Geological Sciences Beijing 100037China Urban Construction School Beijing City UniversityBeijing 100083China

A calamitous landslide happened at 22:00 on September 1,2014 in the Yunyang area of Chongqing City,southwest China,enforcing the evacuation of 508 people and damaging 23 *** landslide volume comprised 1.44 million m^(3) of material in the source area and 0.4 million m^(3) of shoveled *** debris flow runout extended 400 m vertically and 1600 m *** Xianchi reservoir landslide event has been investigated as follows:(1)samples collected from the main body of landslide were carried out using GCTS ring shear apparatus;(2)the parameters of shear and pore water pressure have been measured;and(3)the post-failure characteristics of landslide have been analyzed using the numerical simulation *** excess pore-water pressure and erosion in the motion path are considered to be the key reasons for the long-runout motion and the scale-up of landslides,such as that at Xianchi,were caused by the heavy *** aim of this paper is to acquired numerical parameters and the basic resistance model,which is beneficial to improve simulation accuracy for hazard assessment for similar to potentially dangerous hillslopes in China and elsewhere.

关键词： geohazards landslide post-failure rapid and long runout ring shear test

Synthesis and characteristics of transparent Gd_(2)O_(3)ceramics with cubic structure

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Journal of Advanced Ceramics 2024年第4期13卷 463-468页

作者： Akio Ikesue yan Lin Aung World Lab Co. Nagoya456-8587Japan

Transparent Gd_(2)O_(3)ceramics with a cubic crystal structure were successfully synthesized for the first *** Gd_(2)O_(3)ceramics subjected to hot isostatic press(HIP)at 1070℃consisted of uniform grains of 2-3μm,and only a few residual pores could be detected inside the materials.X-ray diffraction(XrD)shows that the obtained polycrystalline materials have a cubic crystal structure,and the transmission polarized light observation shows that there is no birefringence inside the materials,indicating inherent optical properties of the cubic crystal *** optical absorption edge is 640 nm(optical band gap:2.1 eV),and the transmittance in the visible to near-infrared region is 72%,which is close to the theoretical transmittance calculated from Fresnel *** constant of this material is almost wavelength-independent,and it is diamagnetic since it has the opposite polarity to that of common paramagnetic materials.

关键词： gadolinium oxide cubic hot isostatic press(HiP) diamagnetic Verdet constant

microscale spherical TiO_(2)powder prepared by hydrolysis of TiCl_(4)solution:Synthesis and kinetics

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Particuology 2024年第1期84卷 60-71页

作者： Peiyi yan Ying Zhang Shili Zheng School of rare Earths University of Science and Technology of ChinaHefei230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China Key Laboratory of Green Process and Engineering National Engineering Research Center of Green Recycling for Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing100190China State Key Laboratory of Vanadium and Titanium resources Comprehensive Utilization Panzhihua617000China

Hydrolysis of TiCl_(4)solution is capable of preparing microscale TiO_(2)*** research studied the synthesis of microscale spherical TiO_(2)powders and the hydrolysis *** effects of the flow field generated by different agitators and baffles in the crystallizer,the initial free acid concentration,the initial equivalent TiO_(2)concentration,and the temperature on the hydrolysis progress and powder morphology were systematically *** results show that the flow field in a crystallizer can significantly affect the morphology and particle size of the powders,and the axial flow can improve the sphericity of the *** increased free HCl and equivalent TiO_(2)concentrations in the pregnant solution inhibit the forward hydrolysis reaction,prolong the time to reach equilibrium,and reduce the *** appropriate temperature matching the compositions of the pregnant solution is crucial for the powder morphology and *** with sizes ranging from around 5 um-40μm can be tuned under controlled flow field,solution compositions,and temperature *** addition,the Cheng and Wunderlich modified Avrami equation was used for the crystallization kinetic *** effects of the free HCl concentration,equivalent TiO_(2)concentration,and hydrolysis temperature are reflected in the reaction rate constant and active nuclei reduction *** the free HCl and equivalent TiO_(2)concentrations will reduce the reaction rate constant and accelerate the deactivation of the active nuclei,thus increasing the final powder size,while increasing the temperature will lead to the opposite results.

关键词： TiCl_(4) Hydrolysis microscale TiO_(2) Spherical Kinetics

Effect of dissolved-oxygen on the flotation behavior of pyrite at high altitude area

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International Journal of minerals,metallurgy and materials 2024年第10期31卷 2148-2158页

作者： yan miao Guangke Ye Guofan Zhang School of minerals Processing and Bio-engineering Central South UniversityChangsha 410083China

With the continuous development of mineral resources to high altitude areas,the study of sulfide ore flotation in unconventional systems has been *** is a consensus that moderate oxidation of sulfide ore is beneficial to flotation,but the specific suitable dissolved oxygen value is inconclusive,and there are few studies on sulfide ore flotation under low dissolved oxygen environment at high *** this paper,we designed and assembled an atmosphere simulation flotation equipment to simulate the flotation of pyrite at high altitude by controlling the partial pressure of N_(2)/O_(2) and dissolved oxygen under atmospheric conditions.X-ray photoelectron spec-troscopy(XPS),atomic force microscope(AFm),Fourier transform infrared spectrometer(FT-Ir),UV-vis spectrophotometer,zeta po-tential,and contact angle measurements were used to reveal the effects of surface oxidation and agent adsorption on pyrite at high altitude(4600 m dissolved oxygen(DO)=4.0 mg/L).The results of pure mineral flotation indicated that the high altitude and low dissolved oxy-gen environment is favorable for pyrite *** angle measurements and XPS analysis showed that the high altitude atmosphere nslows down the oxidation of pyrite surface,facilitates S_(n)^(2-)/S^(0) production and enhances surface *** calcula-tions and zeta potential analysis showed that the influence of atmosphere on the form of pyrite adsorption is small,and the different atmo-spheric conditions are consistent with dixanthogen electrochemical adsorption,with lower Zeta potential under high altitude atmosphere and significant potential shift after sodium isobutyl xanthate(SIBX)*** results of FT-Ir,UV-vis,and AFm analysis showed that SIBX adsorbed more on the surface of pyrite under high altitude atmosphere and adsorbed on the surface in a mesh structure com-posed of column/*** results of the experimental study revealed the reasons for the easy flotation of sul

关键词： high altitude dissolved-oxygen pyrite flotation oxidation

High-speed penetration of ogive-nose projectiles into thick concrete targets:Tests and a projectile nose evolution model

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Defence Technology（防务技术） 2024年第2期32卷 553-571页

作者： Xu Li yan Liu Junbo yan Zhenqing Shi Hongfu Wang Yingliang Xu Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China China research and Development Academy of machinery Equipment Beijing100089China

The majority of the projectiles used in the hypersonic penetration study are solid flat-nosed cylindrical projectiles with a diameter of less than 20 *** study aims to fill the gap in the experimental and analytical study of the evolution of the nose shape of larger hollow projectiles under hypersonic *** the hypersonic penetration test,eight ogive-nose Aermet100 steel projectiles with a diameter of 40 mm were launched to hit concrete targets with impact velocities that ranged from 1351 to 1877 m/*** erosion of the projectiles was observed during high-speed penetration of heterogeneous targets,and apparent localized mushrooming occurred in the front nose of recovered *** examining the damage to projectiles,a linear relationship was found between the relative length reduction rate and the initial kinetic energy of projectiles in different penetration ***,microscopic analysis revealed the forming mechanism of the localized mushrooming phenomenon for eroding penetration,i.e.,material spall erosion abrasion mechanism,material flow and redistribution abrasion mechanism and localized radial upsetting deformation ***,a model of highspeed penetration that included erosion was established on the basis of a model of the evolution of the projectile nose that considers radial upsetting;the model was validated by test data from the literature and the present *** upon the impact velocity,v0,the projectile nose may behave as undistorted,radially distorted or *** to the effects of abrasion of the projectile and enhancement of radial upsetting on the duration and amplitude of the secondary rising segment in the pulse shape of projectile deceleration,the predicted DOP had an upper limit.

关键词： High-speed penetration Concrete target Erosion Projectile nose evolution model