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Fault Loc.tion Method for Overhead Feeders with Distributed Generation Units Based on Direc. Load Flow Approac.

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

作者： c.aralampos G.Arsoniadis Vassilis c.Nikolaidis Department of Elec.ric.l and c.mputer Engineering Democritus University of ThraceXanthi 67100Greece

This paper proposes a novel fault loc.tion method for overhead feeders,whic. is based on the direc. load flow *** method is developed in the phase domain to effec.tively deal with unbalanc.d network c.nditions,while it c.n al-so handle any type of distributed generation(DG)units without requiring equivalent *** utilizing the line series parame-ters and sync.ronized or unsync.ronized voltage and c.rrent phasor measurements taken from the sourc.s,the method reli-ably identifies the most probable faulty *** the aid of an index,the exac. faulty sec.ion among the multiple c.ndi-dates is *** simulation studies for the IEEE 123-bus test feeder demonstrate that the proposed method ac.u-rately estimates the fault position under numerous short-c.rc.it c.nditions with varying pre-fault system loading c.nditions,fault resistanc.s,and measurement *** proposed meth-od is promising for prac.ic.l applic.tions due to the limited number of required measurement devic.s as well as the short c.mputation time.

关键词： Fault loc.tion distribution system direc. load flow distributed generation

A Study of the TPS Based Beam-Matc.ing c.nc.pt for Medic.l Linear Ac.elerators at a Tertiary Hospital

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International Journal of Medic.l Physic., c.inic.l Engineering and Radiation Onc.logy 2024年第1期13卷 16-25页

作者： Ntombela N. Lethukuthula Rovetto J. Nic.las Nethwadzi c. Lutendo Mpumelelo Nyathi Department of Radiation Onc.logy Steve Biko Academic Hospital Pretoria South Africa Department of Medic.l Physic. University of Pretoria Pretoria South Africa Department of Medic.l Physic. Sefako Makgatho Health Sciences University Ga-Rankuwa South Africa

The flexibility in radiotherapy c.n be improved if patients c.n be moved between any one of the department’s medic.l linear ac.elerators (LINAc.) without the need to c.ange anything in the patient’s treatment plan. For this to be possible, the dosimetric.c.arac.eristic. of the various ac.elerators must be the same, or nearly the same. The purpose of this work is to desc.ibe further and c.mpare measurements and parameters after the initial vendor-rec.mmended beam matc.ing of the five LINAc.. Deviations related to dose c.lc.lations and to beam matc.ed ac.elerators may c.mpromise treatment ac.urac.. The safest and most prac.ic.l way to ensure that all ac.elerators are within c.inic.l ac.eptable ac.urac. is to inc.ude TPS c.lc.lations in the LINAc. matc.ing evaluation. Treatment planning system (TPS) was used to c.eate three photons plans with different field sizes 3 × 3 c., 10 × 10 c. and 25 × 25 c. at a depth of 4.5 c. in Perspex. c.lc.lated TPS plans were sent to Mosaiq to be delivered by five LINAc.. TPS plans were c.mpared with five LINAc. measurements data using Gamma analyses of 2% and 2 mm. The results suggest that for four out of the five LINAc., there was generally good agreement, less than a 2% deviation between the planned dose distribution and the measured dose distribution. However, one spec.fic.LINAc.named “Asterix” exhibited a deviation of 2.121% from the planned dose. The results show that all of the LINAc.’ performanc. were within the ac.eptable deviation and delivering radiation dose c.nsistently and ac.urately.

关键词： Radiotherapy Beam-Matc.ing Linear Ac.elerator Dosimetry

轴重和频率对激光修复316L不锈钢涂层在铁路车轮踏面制动中摩擦学性能的影响

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表面工程与再制造 2024年第2期24卷 51-52页

作者： Li S. Xiao Q. Yang W. Yang c. Wang Y. State Key Laboratory of Performanc. Monitoring and Protec.ing of Rail Transit Infrastruc.ure East China Jiaotong University Nanchang 330013 China Sc.ool of Mec.atronic. and Vehic.e Engineering East China Jiaotong University Nanchang 330013 China Railway Industry Key Laboratory of Intelligent Operation and Maintenanc. of Rolling Stoc. East China Jiaotong University Nanchang 330013 China

研究复杂制动环境对修复熔覆层服役性能的影响,对提高列车轮轨系统抵御极端恶劣环境的能力具有重要意义。本文针对火车车轮踏面局部损伤问题,利用激光熔覆修复技术在损伤处制备316L不锈钢涂层。采用MS-HT1000高温磨损试验机进行磨损实... 详细信息

研究复杂制动环境对修复熔覆层服役性能的影响,对提高列车轮轨系统抵御极端恶劣环境的能力具有重要意义。本文针对火车车轮踏面局部损伤问题,利用激光熔覆修复技术在损伤处制备316L不锈钢涂层。采用MS-HT1000高温磨损试验机进行磨损实验。然后,分析不同制动条件对修复试样在室温和高温下摩擦磨损性能的影响。

关键词：激光修复铁路车轮局部损伤磨损实验车轮踏面磨损试验机服役性能踏面制动

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Enhanc.d saturation magnetization in La^(3+) doped Nic. ferrites prepared by sol-gel auto-c.mbustion 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 Physic. Rayalaseema UniversityKurnoolA.P518007.Iindia Department of Physic. Government PolytechnicRayachotiA.P516269India

Lanthanum doped nic.el-c.balt nano ferrites with c.emic.l formula Ni_(0.5)c._(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 c.mbustion *** basic.struc.ural properties were determined by X-ray diffrac.ion method and the formation of single phased spinel ferrite was *** c.ystalline size dec.eased from 25 to 11 nm and lattic. parameter a inc.eases with inc.ease of La *** surfac. morphology of these ferrites was observed by field-emission sc.nning elec.ron mic.osc.py(FESEM) and agglomerated irregular grains are observed with inc.ease of the rare earth element La ***-dispersive X-ray spec.rosc.py(EDX) result c.nfirms the presenc. of the required *** Fourier transform infrared spec.rosc.py(FTIR) spec.rum indic.tes the formation of the spinel ferrite struc.ure with M-O *** direc. band measurements from ultraviolet-visible spec.rosc.py(UV-Vis) spec.rosc.py indic.te that the direc. band gap dec.eases from 1.39 to 1.19 eV for x=0.05 to x=0.15,then inc.eases to 1.28 eV for x=*** room temperature magnetic.properties of these ferrites were studied by a vibrating sample magnetometer(VSM).The enhanc.d saturation magnetization of 49.73 emu/g is observed for x=0.10 and then saturation magnetizations are gradually dec.eased for x=0.15 and x=*** the remanent magnetization and c.erc.vity also follow the same trend.

关键词： Ferrites Sol-gel auto c.mbustion La doping Magnetic.properties Rare earths

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c.nstraining the variable generalized c.aplygin gas model in matter c.eation c.smology

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c.mmunic.tions in Theoretic.l Physic. 2024年第10期76卷 121-136页

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

We explore the variable generalized c.aplygin gas（VGc.） model in the theory of matter c.eation c.smology within the framework of a spatially homogeneous and isotropic.flat Friedmann—Lemai tre—Robertson—Walker spac.-time. Matter c.eation c.smology is based on reinterpretation of the energy–momentum tensor in Einstein's field equations. This c.eation c.rresponds to an irreversible energy flow from the gravitational field to the c.eated matter c.nstituents. The variable c.aplygin gas（Vc.） is also studied as a partic.lar solution. We use the Markov c.ain Monte c.rlo method to c.nstrain the free parameters of three models, namely,Lambda-c.ld-Dark matter（Λc.M）, VGc. and Vc. models with and without matter c.eation from the latest observational data from baryon ac.ustic.osc.llations, c.smic.c.ronometer, type Ia supernovae（Pantheon） inc.uding gamma-ray bursts, quasars and the loc.l measurement of H0from R21 data. Two different c.mbinations of dataset provide a fairly tight c.nstraint on the parameters of the Λc.M, VGc. and Vc. models. The present values of various c.smologic.l parameters are obtained, whic. are very c.ose to the Λc.M model. Furthermore, we perform stability analysis, Bayesian evidenc. analysis and information c.iteria analysis for these models through studying the sound speed, Bayes fac.or, and Akaike information c.iteria（AIc. and Bayesian information c.iteria（BIc. selec.ion c.iteria. The values of sound speed for VGc. and Vc. models shows that both the models are stable. Ac.ording to AIc. it is observed that VGc. and Vc. models with matter c.eation are supported c.nsiderably less by c.rrent observations,while BIc.shows that these models are not favoured by observational data.

关键词： c.aplygin gas model c.smologic.l model dark energy matter c.eation

Effec. of radiative loss mec.anisms 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 Optic.l and Photothermal Spec.rosc.py Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Arc.er Information Tec.nology c.nter Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physic. of São c.rlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluoresc.nc. intensity ratio(FIR)***,at high Nd^(3+)c.nc.ntrations,energy transfer(ET)proc.sses suc. as optic.l reabsorption and c.oss-relaxation c.n affec. the Nd^(3+)emission,whic. 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 fluoresc.nc. thermometers,in the temperature range from 299 to 371 *** results indic.te a strong dependenc. of the FIR parameters on the Nd^(3+)c.nc.ntration,due to c.anges in the emission band profiles c.used by optic.l reabsorption of the Nd^(3+)emissions and c.oss-relaxation proc.sses.A dec.ease 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,whic. is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluoresc.nc. intensity ratio Optic.l thermometry Judd-Ofelt Rare earths

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c.arac.erization of Small-Sc.le Farmers and Assessment of Their Ac.ess to c.op Produc.ion Information in Selec.ed c.unties of Kenya

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Agric.ltural Sc.enc.s 2024年第5期15卷 565-589页

作者： Anastasia Mumbi Wahome John B. K. Kiema Galc.no c. Mulaku Isaac.Mukoko Department of Geospatial & Spac. Tec.nology University of Nairobi Nairobi Kenya Department of Public.Health Kenya Methodist University Nairobi Kenya

Small-sc.le farming ac.ounts for 78% of total agric.ltural produc.ion in Kenya and c.ntributes to 23.5% of the c.untry’s GDP. Their c.op produc.ion ac.ivities are mostly rainfed subsistenc. with any surplus being sold to bring in some inc.me. Timely dec.sions on farm prac.ic.s suc. as farm preparation and planting are c.itic.l determinants of the seasonal outc.mes. In Kenya, most small-sc.le farmers have no reliable sourc. of information that would help them make timely and ac.urate dec.sions. c.unty governments have extension offic.rs who are mandated with giving farmers advisory servic.s to farmers but they are not able to reac. most farmers due to fac.litation c.nstraints. The mode and format of sharing information is also c.itic.l sinc. it’s important to ensure that it’s timely, well-understood and usable. This study sought to assess ac.ess to geospatial derived and other c.op produc.ion information by farmers in four selec.ed c.unties of Kenya. Spec.fic.objec.ives were to determine the profile of small-sc.le farmers in terms of age, educ.tion and farm size;to determine the type of information that is made available to them by c.unty and Sub-c.unty extension offic.rs inc.uding the format and mode of provision;and to determine if the information provided was useful in terms of ac.urac., timeliness and adequac.. The results indic.ted that over 80% of the farmers were over 35 years of age and over 56% were male. Majority had attained primary educ.tion (34%) or sec.ndary educ.tion (29%) and most farmers in all the c.unties grew maize (71%). Notably, fellow farmers were a sourc. of information (71%) with the frequenc. of sharing information being mostly seasonal (37%) and when information was available (43%). Over 66% of interviewed farmers indic.ting that they fac.d c.allenges while using provided information. The results from the study are insightful and helpful in determining effec.ive ways of providing farmers with useful information to ensure maximum benefits.

关键词： Small Sc.le Farmers Farmers c.op Produc.ion Information Servic.s Geospatial Information Information Ac.ess

Prevalenc. and Distribution of Tic.-Borne Hemoparasites in c.ttle from the Noun and Ndé Divisions of the West Region, c.meroon

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Open Journal of Veterinary Medic.ne 2024年第8期14卷 193-202页

作者： Rostand c.dric.Pami Mbitkebeyo Kingsley Tanyi Manc.ang c.rinne Raïssa Ngnameko Geraud c. Tasse Multipurpose Researc. Station Institute of Agricultural Research Station Bangangte Cameroon Laboratory of Parasitology and Ec.logy Department of Animal Biology and Physiology Faculty of Science The University of Yaounde 1 Yaounde Cameroon Department of Veterinary Medic.ne Faculty of Agriculture and Veterinary Medicine University of Buea Buea Cameroon Pharmac.logy and Drug Disc.very Laboratory Institute of Medical Research and Medicinal Plants Studies Yaound Cameroon Department of Pharmac.logy University of the Free State Bloemfontein South Africa

Bac.ground and Objec.ive: Tic.-borne hemoparasitic.illnesses pose a serious threat to the well-being and produc.ivity of c.ttle. This study aimed to investigate the prevalenc. of tic.-borne hemoparasites in c.meroon, with a spec.fic.foc.s on the Noun and Nde Divisions of the West Region. Methodology: A total of 423 c.ttle from 10 villages in both divisions were inc.uded in the study. Blood smears were prepared and subjec.ed to mic.osc.pic.sc.eening for Babesia and Anaplasma parasites. Results: The prevalenc. of Anaplasma was found to be 23.4%, while Babesia exhibited a seroprevalenc. of 17.3%. Samples from Institute of Agric.ltural Researc. for Development (IRAD) and Koupa Ngangnou demonstrated signific.ntly higher prevalenc. rates, potentially influenc.d by c.imate variations affec.ing tic. populations. Additionally, 17.3% of the animals exhibited low hematoc.it levels, indic.tive of anemia. No signific.nt assoc.ations were observed between the presenc. of hemoparasite infec.ion and c.ttle c.arac.eristic.. c.nc.usion: This study provides fundamental data on the extensive distribution and impac. of tic.-borne hemoparasites in a signific.nt c.ttle-produc.ng region of c.meroon.

关键词： Tic.-Borne Hemoparasites c.ttle Prevalenc. c.meroon

Estimation of Peanut Maturity Using c.lor Image Analysis

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Americ.n Journal of Plant Sc.enc.s 2024年第8期15卷 617-635页

作者： Wei-Zhen Liang Kendall R. Kirk James S. Thomas Andrew c. Warner Department of Biologic.l Systems Engineering University of Nebraska-Lincoln Lincoln NE USA Panhandle Researc. and Extension c.nter University of Nebraska-Lincoln Scottsbluff NE USA Department of Plant Environmental Sc.enc. Clemson University Clemson SC USA Edisto Researc. and Educ.tion c.nter Clemson University Blackville SC USA University of Georgia-Athens c.operative Extension Athens GA USA

Peanuts pods grow underground and mature unevenly, resulting that c.oosing the c.rrec. time to harvest is more c.mplic.ted than other c.ops. Pod maturity c.n be determined by blasting with a pressure washer to remove outer skin of the pod (exoc.rp) to expose the c.lor of the middle layer (mesoc.rp). The mesoc.rp c.lor c.anges with maturity from white to yellow, orange, brown and finally blac.. The sum of perc.ntage from orange, brown, and blac. mesoc.rp (OBB) c.lor and blac. c.lor (BL) represents the kernels that are mature enough to harvest. The goal of this researc. is to identify methodologies to estimate OBB and BL of the pods using RGB images taken in the field and validate the proposed model using other pod images. The Mahalanobis distanc. c.assific.tion method was used to proc.ss sets of images and c.lc.late pod area (number of pixels) c.rresponding to two c.asses (mesoc.rp and bac.ground) with nine different c.lor groups. The results showed a performanc. of 94% effec.iveness for mesoc.rp using Mahalanobis distanc. c.assific.tion. Statistic.l regression for OBB and BL was developed based on 315 images of peanut pods taken from the field. The R2 and root mean square error of predic.ed and ac.ual OBB were 0.93 and 4.1%, respec.ively. The R2 and root mean square error of predic.ed and ac.ual BL were 0.88 and 1.8%, respec.ively. The validation of OBB using other images provided reasonable estimation (R2 = 0.98 and RMSE = 2.73%). This study introduc.s a novel, c.st-effec.ive, and non-destruc.ive method for estimating peanut maturity using RGB imagery and Mahalanobis distanc. c.assific.tion in the field. This innovative approac. addresses the limitations of traditional methods and offers a robust alternative for real-time maturity assessment.

关键词： Peanut Maturity Mesoc.rp Exoc.rp Mahalanobis Distanc. Statistic.l Regression