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PV Maximum Power-point Tracking Using Modified Particle Swarm Optimization under Partial Shading Conditions

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Chinese Journal of Electrical Engineering 2020年第4期6卷 106-121页

作者： Al-wesabi Ibrahim M.B.Shafik Min Ding Mohammad Abu Sarhan Zhijian Fang Ahmed.g.Alareqi Tariq Al’moqri Ayman.M.Al-Rassas School of Automation China University of GeoscienceWuhan 430074China Hubei key laboratory of Advanced Control and Intelligent Automation for Complex systems Wuhan 430074China School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China School of Oil and Natural gas Engineering China University of GeosciencesWuhan 430074China School of Mathematics and Physics China University of GeoscienceWuhan 430074China School of Petroleum Engineering China University of PetroleumEast ChinaQingdao 266580China

A novel maximum power-point tracking approach is proposed based on studies investigating the output characteristics of photovoltaic(PV)systems under partial shading *** existence of partially shaded conditions leads to the presence of several peaks on PV curves,which decrease the efficiency of conventional ***,the proposed algorithm,which is based on the modified particle-swarm optimization(MPSO)technique,increases the output power of PV systems under such abnormal conditions and has a better performance compared to other *** proposed method is examined under several scenarios for partial shading condition and non-uniform irradiation levels using Matlab,and to investigate its effectiveness adequately,the results of the proposed method are compared with those of the neural network *** experimental results show that the proposed method can decrease the interference of the local maximum power-point to cause the PV system to operate at a global maximum *** efficiency of the MPSO is achieved with the least number of steady-state oscillations under partial shading conditions compared with the neural network method.

关键词： Photovoltaic(PV) maximum power point tracking(MPPT) step-up converter artificial neural networks(ANNs) particle-swarm optimization(PSO)

Influence of warm eddies on sound propagation in the gulf of Mexico

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Chinese Physics B 2019年第5期28卷 134-144页

作者： Yao Xiao Zhenglin Li Jun Li Jiaqi Liu state key laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences university of Chinese Academy of Sciences China state Shipbuilding Corporation (CSSC) systems Engineering Research Institute College of Underwater Acoustic Engineering Harbin Engineering University Woodruff School Mechanical Engineering Georgia Institute of Technology

An automatic detection method is employed to identify and track eddies in the gulf of Mexico. The physical parameters of the eddies, such as lifespan, radius, and distribution position are first examined and used to determine the spatio–temporal evolution of a strong warm eddy separated from the Mexico current. Then, the influence of this strong warm eddy on sound propagation during its lifespan are comprehensively analyzed with the parabolic equation and explained by using the normal mode and ray theories. Additionally, the influence of mesoscale eddies on the redistribution of total depth-integrated energy among the normal modes in the deep water is also discussed. The variation of arrival angle is investigated to explain the spreading acoustic energy caused by eddies. Overall, the results show that warm eddies can change the propagation paths and cause the convergence zone to broaden and approach the sound source. Moreover,the warm eddy can disperse sound energy and cause the total depth-integrated energy to incline to a lower normal *** the whole of these three periods(eddy generating, eddy maturing, and eddy terminating), the fluctuation in the transmission loss is up to 30 dB(depending on the relative location of eddy center to the source).

关键词： mesoscale eddies sound propagation mode coupling acoustic energy disturbance

Modelling virtual Realities:virtual reality as a Transformative technology for the Humanities

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比较文学与跨文化研究 2020年第1期 19-30页

作者： Øyvind Eide Zoe Schubert Jan g.Wieners Institute for Digital Humanities University of Cologne

This paper proposes bridging virtual reality(VR)and the humanities,creating a valuable outcome through the implementation of virtual realities in teaching environments and through the reflection on the narratives and content in the process of modelling in the *** state of the art technologies offer many people the opportunity to experience VR without having to purchase expensive *** results in a rapidly growing number of different content to explore,and a diversification of overall *** at VR as a form of representation and as a means of reproducing narratives,many potential research questions also for the(digital)humanities *** includes observing,exploring and comprehending the modelling of virtual *** is of key importance to consider the process of creation,which is a process of modelling done by different individuals with different disciplinary *** courses at the university of Cologne were offered in which virtual worlds for the narration of theatre plays as well as other narratives were modelled by the *** experiences from these courses will be used to analyse critically the use of VR in the humanities.

关键词： Digital Humanities virtual reality Modelling Media Transformation Experimental Teaching Theatre Cardboard

MICROBRIDgE TESTINg OF YOUNg'S MODULUS AND RESIDUAL STRESS OF NICKEL FILM ELECTROPLATED ON SILICON WAFER

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 247-254页

作者： Y.Zhou C.S.Yang J.A. Chen g.F. Ding L. Wang M.J Wang Y.M Zhang T.H Zhang key laboratory for Thin Film and Microfabrication of Ministry of Education Research Institute of Micro/Nanometer Science and Technology Shanghai Jiaotong University Shanghai 200030 China state key laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics The Chinese Academy of Sciences Beijing 100080 China.

Microbridge testing is used to measure the Young's modulus and residual stresses of metallic *** film microbridges with widths of several hundred microns are fabricated by Microelectromechanical *** order to measure the mechanical properties of nickel film microbridges,special shaft structure is designed to solve the problem of getting the load--deflection curves of metal film microbridge by Nanoin--denter XP system with normal Berkovich *** analysis of the micro--bridge load--deflection curve is proposed to evaluate the Young's modulus and residual stress of the films *** calculated results based on the experimental measurements show that the average Young's modulus and residual stress are around 190gPa and 175MPa respectively,while the Young's modulus measured by Nano-hardness method on nickel film with silicon substrate is 186.8±7.34gPa.

关键词： nickel film microbridge MEMS mechanical property loadeflection measurement

Spectral emittance measurements of micro/nanostructures in energy conversion:a review

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Frontiers in Energy 2020年第3期14卷 482-509页

作者： Shiquan SHAN Chuyang CHEN Peter g.LOUTZENHISER Devesh RANJAN Zhijun ZHOU Zhuomin M.ZHANg state key laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China george W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta GA 30332USA

Micro/nanostructures play a key role in tuning the radiative properties of materials and have been applied to high-temperature energy conversion systems for improved *** the various radiative properties,spectral emittance is of integral importance for the design and analysis of materials that function as radiative absorbers or *** paper presents an overview of the spectral emittance measurement techniques using both the direct and indirect ***,several micro/nanostructures are also introduced,and a special emphasis is placed on the emissometers developed for characterizing engineered micro/nanostructures in high-temperature applications(e.g.,solar energy conversion and thermophotovoltaic devices).In addition,both experimental facilities and measured results for different materials are ***,future prospects in developing instrumentation and micro/nanostructured surfaces for practical applications are also *** paper provides a comprehensive source of information for the application of micro/nanostructures in high-temperature energy conversion engineering.

关键词： concentrating solar power(CSP) emittance measurements high temperature micro/nanostructure selective absorber selective emitter thermophotovoltaics(TPV)

Two-beam phase correlation spectroscopy:a label-free holographic method to quantify particle flow in biofluids

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Photonics Research 2023年第5期11卷 757-764页

作者： LAN YU YU WANg YANg WANg KEQUN ZHUO MIN LIU g.ULRICH NIENHAUS PENg gAO School of Physics Xidian UniversityXi’an 710071China Institute of Applied Physics Karlsruhe Institute of Technology76128 KarlsruheGermany Institute of Nanotechnology Karlsruhe Institute of Technology76344 Eggenstein-LeopoldshafenGermany Institute of Biological and Chemical systems Karlsruhe Institute of Technology76344 Eggenstein-LeopoldshafenGermany Department of Physics University of Illinois at Urbana-ChampaignUrbanaIllinois 61801USA

We introduce two-beam phase correlation spectroscopy(2B-ΦCS)as a label-free technique to measure the dynamics of flowing particles;e.g.,in vitro or in vivo blood flow.2B-ΦCS combines phase imaging with correlation spectroscopy,using the intrinsic refractive index contrast of particles against the fluid background in correlation *** method starts with the acquisition of a time series of phase images of flowing particles using partially coherent point-diffraction digital holographic ***,phase fluctuations from two selected circular regions in the image series are correlated to determine the concentration and flow velocity of the particles by fitting pair correlation curves with a physical model.2B-ΦCS is a facile procedure when using a microfluidic channel,as shown by the measurements on flowing yeast microparticles,polymethyl methacrylate microparticles,and diluted rat *** the latter experiment,the concentration and average diameter of rat blood cells were determined to be(4.7±1.9)×10^(6)μL^(-1)and 4.6±0.4μm,*** further analyzed the flow of mainly red blood cells in the tail vessels of live zebrafish *** and venous flow velocities were measured as290±110μm s^(-1)and 120±50μm s^(-1),*** envision that our technique will find applications in imaging transparent organisms and other areas of the life sciences and biomedicine.

关键词： flow flow holographic

Two-stage Hall-Petch relationship in Cu with recrystallized structure

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Journal of Materials Science & technology 2020年第13期47卷 31-35页

作者： Y.Z.Tian Y.P.Ren S.gao R.X.Zheng J.H.Wang H.C.Pan Z.F.Zhang N.Tsuji g.W.Qin key laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China state key laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Department of Materials Science and Engineering Kyoto UniversityYoshida-honmachiSakyo-kuKyoto 606-8501Japan Elements Strategy Initiative for Structural Materials(ESISM) Kyoto UniversityYoshida-honmachiSakyo-kuKyoto606-8501Japan key laboratory of Aerospace Advanced Materials and Performance of Ministry of Education School of Materials Science and EngineeringBeihang UniversityBeijing 100191China state grid Urban and Rural Electric Power Design Research(beijing)Co.Ltd Beijing 100078China laboratory of Fatigue and Fracture for Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

Although Cu was studied extensively,the Hall-Petch relationship was mainly reported in the coarsegrained *** this work,fully recrystallized Cu specimens with a wide grain size regime of 0.51–14.93μm manifest a two-stage Hall-Petch *** is a critical grain size of 3μm that divides stagesⅠandⅡwhere the Hall-Petch slope k value are quite *** stageⅡis supposed to be validified down to 100 nm at least by comparing with a Cu-Ag *** critical grain size varies in different materials systems,and the underline mechanisms are discussed based on the dislocation glide modes.

关键词： Cu Yield strength Hall-Petch relationship Ultrafine grain Recrystallization

Epigenetic modification mechanisms of chloroplasts mutants in pineapple leaves during somatic regeneration

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Horticultural Plant Journal 2023年第3期9卷 509-522页

作者： Yanhui Liu S.V.g.N.Priyadarshani Meirong Chi Maokai Yan Mohammad Aqa Mohammadi Man Zhang Qiao Zhou Lulu Wang Tiantian Luo Myat Hnin Wai Xiaomei Wang Hanyang Cai Haifeng Wang Yuan Qin College of Life Sciences Key Lab of GeneticsBreeding and Multiple Utilization of CropsMinistry of EducationFujian Provincial Key Laboratory of Haixia Applied Plant Systems BiologyCenter for Genomics and BiotechnologyFujian Agriculture and Forestry UniversityFuzhouFujian 350002China College of Life Science Longyan UniversityLongyanFujian 364012China guangxi key laboratory of Sugarcane Biology State Key Laboratory for Conservation and Utilization of Subtropical Agro-BioresourcesCollege of AgricultureGuangxi UniversityNanningGuangxi 530004China Horticulture Research Institute Guangxi Academy of Agricultural SciencesNanning Investigation Station of South Subtropical Fruit TreesMinistry of AgricultureNanningGuangxi 530007China Pingtan Science and technology Research Institute of Fujian Agriculture and Forestry university FuzhouFujian 350002China National Education Commission Sri Lanka

Somaclonal variation in tissue culture is a common phenomenon induced by various external or internal environmental conditions,resulting in heritable or non-heritable alterations in gene expression. One crucial mechanism involved in plant growth and development is epigenetic regulation. A highly dynamic epigenome can respond to environmental changes by regulating gene expression. DNA methylation is one of these epigenetic modifications that can alter gene expression in tissue-cultured pineapple plants. The underlying mechanism of such somaclonal variations in pineapple and the epigenetic regulation involvement in somaclonal variations has not been studied. This study performed DNA methylome and transcriptome sequencing of wild-type(WT) and mutant pineapple plants(WS, HW, and TW). We observed altered DNA methylation patterns in chlorophyll development in the mutants. Specifically, we noticed that the methylation levels in the CHg and CHH contexts were lower in the gene body regions compared to the upstream and downstream regions. We identified several thousand differentially methylated regions(DMRs) located at the gene body regions, some of which overlapped with the differentially expressed genes(DEgs). Functional enrichment analyses suggested that these genes were involved in chlorophyll metabolism. Thus, our results revealed that the transcriptional regulation of many chlorophyll metabolic essential genes could be regulated by DNA methylation caused by somaclonal variations and provided insights into epigenetic mechanisms underlying the regulation of chlorosis in pineapple plants.

关键词： Pineapple DNA methylation Transcriptome Chlorophyll metabolism

SAFETY HAZARD AND DAMAgE RISKS FOR MONOLITHIC WINDOW gLAZINg SUBJECT TO EXPLOSIVE BLAST LOADINg

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SAFETY HAZARD AND DAMAGE RISKS FOR MONOLITHIC WINDOW GLAZING...