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Fault Location Method for Overhead Feeders with Distributed Generation Units Based on Direct Load Flow Approach

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Journal of Modern Power Systems and clean Energy 2024年第4期12卷 1135-1146页

作者： charalampos G.Arsoniadis Vassilis c.Nikolaidis Department of Electrical and computer Engineering Democritus University of ThraceXanthi 67100Greece

This paper proposes a novel fault location method for overhead feeders,which is based on the direct load flow *** method is developed in the phase domain to effec-tively deal with unbalanced network conditions,while it can al-so handle any type of distributed generation(DG)units without requiring equivalent *** utilizing the line series parame-ters and synchronized or unsynchronized voltage and current phasor measurements taken from the sources,the method reli-ably identifies the most probable faulty *** the aid of an index,the exact faulty section among the multiple candi-dates is *** simulation studies for the IEEE 123-bus test feeder demonstrate that the proposed method accu-rately estimates the fault position under numerous short-circuit conditions with varying pre-fault system loading conditions,fault resistances,and measurement *** proposed meth-od is promising for practical applications due to the limited number of required measurement devices as well as the short computation time.

关键词： Fault location distribution system direct load flow distributed generation

Experimental and numerical analysis of multi-chamber oscillating water column devices

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Journal of Hydrodynamics 2024年第3期36卷 492-503页

作者： Jorge Gadelho Kourosh rezanejad c.Guedes Soares centre for Marine Technology and Ocean Engineering(cENTEc) Instituto Superior TécnicoUniversidade de LisboaAvenida Rovisco PaisLisboaPortugal

A review of multi-chamber oscillating water column(OWc)device designs is *** significant variations of these devices are discussed,onshore OWc(OOWc)and a floating OWc(FOWc).The efficiency results of several theoretical studies based on low-and high-fidelity numerical models are presented and compared with the model scale ***,low-fidelity numerical models are very fast to run,but their accuracy is limited compared with high-fidelity numerical *** model experiments usually give results much more accurate than numerical models,but they need adequate facilities and are very *** the case of the OOWc,all models show a similar trend of total efficiency,but while the analytical model shows a maximum value of around 90%efficiency,the cFD model shows 60%,and the experiments only go up to 40%.The main reason is connected with the mathematical simplifications and assumptions that do not represent all the hydrodynamic and aerodynamic processes between the water,air,and *** the case of the FOWc,interestingly,the experimental results show a maximum efficiency of almost 100%,while the analytical model only predicts a maximum of 80%.The efficiency seems highly dependent on the heave motion resonance of the entire device,where the analytical model fails to predict this natural frequency.

关键词： Wave energy converters oscillating water column(OWc) multi-chambers experimental modelling numerical modelling

Enhanced saturation magnetization in La^(3+) doped Nico ferrites prepared by sol-gel auto-combustion method

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Journal of Rare Earths 2024年第8期42卷 1546-1554,I0005页

作者： Maddileti Jelli Vidyasagar Thopudurthy Krishna reddy c.V. Department of Physics Rayalaseema UniversityKurnoolA.P518007.Iindia Department of Physics Government PolytechnicRayachotiA.P516269India

Lanthanum doped nickel-cobalt nano ferrites with chemical formula Ni_(0.5)co_(0.5)LaxFe_(2-x)O_(4)(x=0.05,0,10,0.15 and 0,20) were prepared using a simple sol-gel auto combustion *** basic structural properties were determined by X-ray diffraction method and the formation of single phased spinel ferrite was *** crystalline size decreased from 25 to 11 nm and lattice parameter a increases with increase of La *** surface morphology of these ferrites was observed by field-emission scanning electron microscopy(FESEM) and agglomerated irregular grains are observed with increase of the rare earth element La ***-dispersive X-ray spectroscopy(EDX) result confirms the presence of the required *** Fourier transform infrared spectroscopy(FTIR) spectrum indicates the formation of the spinel ferrite structure with M-O *** direct band measurements from ultraviolet-visible spectroscopy(UV-Vis) spectroscopy indicate that the direct band gap decreases from 1.39 to 1.19 eV for x=0.05 to x=0.15,then increases to 1.28 eV for x=*** room temperature magnetic properties of these ferrites were studied by a vibrating sample magnetometer(VSM).The enhanced saturation magnetization of 49.73 emu/g is observed for x=0.10 and then saturation magnetizations are gradually decreased for x=0.15 and x=*** the remanent magnetization and coercivity also follow the same trend.

关键词： Ferrites Sol-gel auto combustion La doping Magnetic properties Rare earths

constraining the variable generalized chaplygin gas model in matter creation cosmology

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communications in Theoretical Physics 2024年第10期76卷 121-136页

作者： Yogesh Bhardwaj c P Singh Department of Applied Mathematics Delhi Technological University

We explore the variable generalized chaplygin gas（VGcG） model in the theory of matter creation cosmology within the framework of a spatially homogeneous and isotropic flat Friedmann—Lemai tre—Robertson—Walker space-time. Matter creation cosmology is based on reinterpretation of the energy–momentum tensor in Einstein's field equations. This creation corresponds to an irreversible energy flow from the gravitational field to the created matter constituents. The variable chaplygin gas（VcG） is also studied as a particular solution. We use the Markov chain Monte carlo method to constrain the free parameters of three models, namely,Lambda-cold-Dark matter（ΛcDM）, VGcG and VcG models with and without matter creation from the latest observational data from baryon acoustic oscillations, cosmic chronometer, type Ia supernovae（Pantheon） including gamma-ray bursts, quasars and the local measurement of H0from R21 data. Two different combinations of dataset provide a fairly tight constraint on the parameters of the ΛcDM, VGcG and VcG models. The present values of various cosmological parameters are obtained, which are very close to the ΛcDM model. Furthermore, we perform stability analysis, Bayesian evidence analysis and information criteria analysis for these models through studying the sound speed, Bayes factor, and Akaike information criteria（AIc） and Bayesian information criteria（BIc） selection criteria. The values of sound speed for VGcG and VcG models shows that both the models are stable. According to AIc, it is observed that VGcG and VcG models with matter creation are supported considerably less by current observations,while BIc shows that these models are not favoured by observational data.

关键词： chaplygin gas model cosmological model dark energy matter creation

Assessment of earthquake location uncertainties for the design of local seismic networks

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Earthquake Science 2024年第5期37卷 415-433页

作者： Antonio Fuggi Simone re Giorgio Tango Sergio Del Gaudio Alessandro Brovelli Giorgio cassiani Isamgeo Italia S.r.l. Gallarate 21013Italy STOGIT S.p.A. UnitàGiacimentiCrema 26013Italy Dipartimento di Geoscienze Universitàdegli Studi di PadovaPadova 35131Italy

The ability to estimate earthquake source locations,along with the appraisal of relevant uncertainties,is paramount in monitoring both natural and human-induced *** this purpose,a monitoring network must be designed to minimize the location errors introduced by geometrically unbalanced *** this study,we first review different sources of errors relevant to the localization of seismic events,how they propagate through localization algorithms,and their impact on *** then propose a quantitative method,based on a Monte carlo approach,to estimate the uncertainty in earthquake locations that is suited to the design,optimization,and assessment of the performance of a local seismic monitoring *** illustrate the performance of the proposed approach,we analyzed the distribution of the localization uncertainties and their related dispersion for a highly dense grid of theoretical hypocenters in both the horizontal and vertical directions using an actual monitoring network *** results expand,quantitatively,the qualitative indications derived from purely geometrical parameters(azimuthal gap(AG))and classical detectability *** proposed method enables the systematic design,optimization,and evaluation of local seismic monitoring networks,enhancing monitoring accuracy in areas proximal to hydrocarbon production,geothermal fields,underground natural gas storage,and other subsurface *** approach aids in the accurate estimation of earthquake source locations and their associated uncertainties,which are crucial for assessing and mitigating seismic risks,thereby enabling the implementation of proactive measures to minimize potential *** an operational perspective,reliably estimating location accuracy is crucial for evaluating the position of seismogenic sources and assessing possible links between well activities and the onset of seismicity.

关键词： network design earthquake localization detectability localization uncertainties local seismic network

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.L Silva L.A.O.Nunes S.M.Lima L.H.c.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

contribution of SAR Radar Imagery in the Detection of Suspicious Vessels in the Ivorian EEZ

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World Journal of Engineering and Technology 2024年第1期12卷 200-212页

作者： Koffi cyprien Yoboue Jean-Baptiste Kassi Eric Valère Djagoua Tiemelé Jacque-André Laboratory of remote Sensing and GIS University Center for Research and Application in Remote Sensing (CURAT) Félix Houphouet-Boigny University of Abidjan Cocody Ivory Coast

The present work proposed a method for match SAR and AIS data to detect vessels carrying out suspicious activity in the Ivorian EEZ. Two superposition methods, detected AIS and SAR data, based on point-to-point association on the one hand and point-to-line on the other hand, were used to detect suspicious vessels in Ivorian marine waters. The results showed that most vessels detected in the Ivorian EEZ do not declare their positions to avoid being spotted. These funds are likely to practice illegal, undeclared and unregulated fishing (INN fishing). This clandestine activity is very recurrent in Ivorian waters. This is illustrated by the number of suspicious vessels detected by SAR radar imagery which is greater compared to declared or authorized vessels.

关键词： INN Fishing cFAR Algorithm AIS Sentinel-1A Ivory coast

Unveiling the shadows: a qualitative exploration of barriers to rooftop solar photovoltaic adoption in residential sectors

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clean Energy 2024年第5期8卷 218-228页

作者： Tony c.Mathew Sridevi Nagaraja Pandian School of commerce Kumaraguru College of Liberal Arts and ScienceCoimbatore 641035Tamil NaduIndia

In the face of global climate change,the urgent shift towards renewable energy sources such as solar power is vital for reducing greenhouse gas emissions and fostering a sustainable future,presenting a universal challenge and opportunity for energy policy ***’s adoption of rooftop solar photovoltaic is pivotal due to its vast solar potential,which aligns with national goals to increase renewable energy capacity,reduce carbon emissions,and achieve energy ***’s geographical location offers abundant solar potential,making it a prime candidate for the adoption of rooftop solar photovoltaic *** with the state’s strong commitment to renewable energy initiatives such as the ambitious“SOURA”(solar subsidy program by the Kerala State Electricity Board)project and various incentives for solar adoption,Kerala stands at the forefront of India’s transition towards sustainable energy *** the barriers to rooftop solar photovoltaic adoption in Kerala is crucial for tailoring ef-fective policies and strategies that address specific hindrances from economic constraints to informational *** study employs a qualitative research method to identify the barriers to rooftop solar photovoltaic adoption among households in *** face-to-face interviews with a purposively selected sample of 52 households,the research aims to gain in-depth insights into the multifaceted challenges hindering the widespread adoption of solar energy in residential *** findings reveal several key barriers:financial barriers,informational barriers,technical barriers,regulatory barriers,social barriers,and psychological *** analysis indicates that while there is a predominantly positive attitude towards solar photovoltaic adoption,there are sig-nificant concerns that still need to be *** these barriers with targeted policy interventions and public awareness campaigns could significantly enhance the adoptio

关键词： rooftop solar photovoltaic adoption barriers to solar energy residential solar systems Kerala solar initiatives qualitative analysis in renewable energy

喀麦隆西南部Mamelles条带状铁建造元素地球化学特征

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海洋科学 2024年第7期48卷 47-56页

作者： SOH TAMEHE Landry GANNO Sylvestre 陈祖兴 ROSIÈre carlos Alberto 中国有色桂林矿产地质研究院有限公司广西桂林541004 Department of Earth Sciences University of Yaounde I812 YaoundeCameroon 中国科学院海洋研究所山东青岛266071 Department of Geology Universidade Federal de Minas Gerais31270-901 Belo HorizonteMinas GeraisBrazil

Mamelles铁矿床位于喀麦隆南部刚果克拉通西北缘,距离克里比地区东南方向约20km。该矿床由大规模、高品位磁铁矿矿体组成,赋存于Nyong杂岩体的条带状铁建造(BIF)中。该矿床中的BIF与角闪岩和片麻岩相伴生。在详细的野外调查基础上,我们... 详细信息

Mamelles铁矿床位于喀麦隆南部刚果克拉通西北缘,距离克里比地区东南方向约20km。该矿床由大规模、高品位磁铁矿矿体组成,赋存于Nyong杂岩体的条带状铁建造(BIF)中。该矿床中的BIF与角闪岩和片麻岩相伴生。在详细的野外调查基础上,我们获取了BIF的全岩地球化学数据,并用以约束它们的物质来源和沉积环境。弱正铕(Eu)异常(δEu=2.14~3.55)表明高温热液流体对MamellesBIF的贡献是通过海底火山岩蚀变作用的方式,并有少量碎屑物质输入。正铈(ce)异常的缺失表明,这些BIF可能沉积在缺氧的深海环境中,如火山弧或弧后盆地深水区。

关键词：刚果克拉通喀麦隆 Mamelles铁矿条带状铁建造地球化学