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Predicting grain size-dependent superplastic properties in friction stir processed ZK30 magnesium alloy with machine learning methods

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Journal of Magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： Farid Bahari-Sambran fernando Carreno C.M.Cepeda-Jiménez Alberto Orozco-Caballero Physical Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of Mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The aim of this work is to predict,for the first time,the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models,random forest(RF)and artificial neural network(ANN).With that purpose,a ZK30 magnesium alloy was friction stir processed(FSP)using three different severe conditions to obtain fine grain microstructures(with average grain sizes between 2 and 3μm)prone to extensive superplastic *** three friction stir processed samples clearly deformed by grain boundary sliding(GBS)deformation mechanism at high *** maximum elongations to failure,well over 400% at high strain rate of 10^(-2)s^(-1),were reached at 400℃ in the material with coarsest grain size of 2.8μm,and at 300℃ for the finest grain size of 2μ***,the superplastic response decreased at 350℃ and 400℃ due to thermal instabilities and grain coarsening,which makes it difficult to assess the operative deformation mechanism at such *** work highlights that the machine learning models considered,especially the ANN model with higher accuracy in predicting flow stress values,allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： Machine learning Artificial intelligence Magnesium alloys Superplasticity Friction stir processing Grain coarsening

Stochastic seismic inversion and Bayesian facies classification applied to porosity modeling and igneous rock identification

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Petroleum Science 2024年第2期21卷 918-935页

作者： Fábio Júnior Damasceno Fernandes Leonardo Teixeira Antonio fernando Menezes Freire Wagner Moreira Lupinacci Exploratory Interpretation and Reservoir Characterization Group(GIECAR) Department of Geology and GeophysicsFederal Fluminense UniversityNiter oiRJ24210-346Brazil Petrobras Rio de JaneiroRJ20231-030Brazil National Institute of Science and Technology of Petroleum Geophysics(INCT-GP/CNPQ) Niter oiRJ24210-346Brazil

We apply stochastic seismic inversion and Bayesian facies classification for porosity modeling and igneous rock identification in the presalt interval of the Santos Basin. This integration of seismic and well-derived information enhances reservoir characterization. Stochastic inversion and Bayesian classification are powerful tools because they permit addressing the uncertainties in the model. We used the ES-MDA algorithm to achieve the realizations equivalent to the percentiles P10, P50, and P90 of acoustic impedance, a novel method for acoustic inversion in presalt. The facies were divided into five: reservoir 1,reservoir 2, tight carbonates, clayey rocks, and igneous rocks. To deal with the overlaps in acoustic impedance values of facies, we included geological information using a priori probability, indicating that structural highs are reservoir-dominated. To illustrate our approach, we conducted porosity modeling using facies-related rock-physics models for rock-physics inversion in an area with a well drilled in a coquina bank and evaluated the thickness and extension of an igneous intrusion near the carbonate-salt interface. The modeled porosity and the classified seismic facies are in good agreement with the ones observed in the wells. Notably, the coquinas bank presents an improvement in the porosity towards the top. The a priori probability model was crucial for limiting the clayey rocks to the structural lows. In Well B, the hit rate of the igneous rock in the three scenarios is higher than 60%, showing an excellent thickness-prediction capability.

关键词： Stochastic inversion Bayesian classification Porosity modeling Carbonate reservoirs Igneous rocks

Nonlinear Model Predictive Controller for Compensations of Single Line-to-ground Fault in Resonant Grounded Power Distribution Networks

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1113-1125页

作者： Warnakulasuriya Sonal Prashenajith fernando Mostafa Barzegar-Kalashani Md Apel Mahmud Shama Naz Islam Nasser Hossenzadeh Faculty of Engineering and Environment Northumbria UniversityNewcastleUK School of Software and Electrical Engineering Swinburne University of TechnologyHawthornAustralia School of Engineering Deakin UniversityWaurn PondsAustralia

An nonlinear model predictive controller(NMPC)is proposed in this paper for compensations of single line-to-ground(SLG)faults in resonant grounded power distribution networks(RGPDNs),which reduces the likelihood of power line bushfire due to electric *** current compensation(RCC)inverters with arc suppression coils(ASCs)in RGPDNs are controlled using the proposed NMPC to provide appropri-ate compensations during SLG *** proposed NMPC is incorporated with the estimation of ASC inductance,where the estimation is carried out based on voltage and current measure-ments from the neutral point of the power distribution *** compensation scheme is developed in the discrete time using the equivalent circuit of *** proposed NMPC for RCC inverters ensures that the desired current is in-jected into the neutral point during SLG faults,which is veri-fied through both simulations and control hardware-in-the-loop(CHIL)*** results are also presented against an integral sliding mode controller(ISMC)by demon-strating the capability of power line bushfire mitigation.

关键词： Fault current phase voltage nonlinear model predictive controller(NMPC) parameter adaptation parametric uncertainty power line bushfire

Predicting outcomes after kidney transplantation: Can Pareto’s rules help us to do so?

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World Journal of Transplantation 2024年第1期14卷 9-11页

作者： fernando M Gonzalez Francisca Gonzalez Cohens Department of Nephrology Faculty of MedicineUniversidad de ChileSantiago 7500922Chile Web Intelligence Centre Faculty of Physics and Mathematical SciencesSantiago 7500922Chile

Kidney transplantation is the best option for kidney replacement therapy,even considering that most of the times the grafts do not survive as long as their *** the Khalil et al's experience,published in this issue of the Journal,they analyze their second kidney graft survival and describe those significant predictors of early *** editorial comments on the results and put in perspective that most of the times,long-term graft survival could be inadvertently jeopardized if the immunosuppressive therapy is reduced or withdrawn for any reason,and that it could happen frequently if the transplant physician intends to innovate with the clinical care without proper evidence-based data.

关键词： Kidney transplantation Graft survival Acute rejection Interstitial fibrosis and tubular atrophy Immunosuppression

Secondary rectal linitis plastica caused by prostatic adenocarcinoma-magnetic resonance imaging findings and dissemination pathways:A case report

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World Journal of Radiology 2024年第9期16卷 473-481页

作者： Andres Antonio Labra Giancarlo Schiappacasse Rolando alfonso Cocio Jorge Tomás Torres fernando Omar González Joaquin Alberto Cristi Marcela Schultz Department of Radiology Facultad de Medicina Clínica Alemana-Universidad del DesarrolloSantiago 7650568Región MetropolitanaChile Department of Pathology Clínica Alemana de SantiagoSantiago 7650568Región MetropolitanaChile

BACKGROUND Secondary rectal linitis plastica(RLP)from prostatic adenocarcinoma is a rare and poorly understood form of metastatic spread,characterized by a desmoplastic response and concentric rectal wall infiltration with mucosal *** complicates endoscopic diagnosis and can mimic gastrointestinal *** case series underscores the critical role of magnetic resonance imaging(MRI)in identifying the distinct imaging features of RLP and highlights the importance of considering this condition in the differential diagnosis of patients with a history of prostate *** SUMMARY Three patients with secondary RLP due to prostatic adenocarcinoma presented with varied clinical *** first patient,a 76-year-old man with advanced prostate cancer,had rectal pain and *** showed diffuse prostatic invasion and significant rectal wall thickening with a characteristic"target sign"*** second,a 57-year-old asymptomatic man with elevated prostatespecific antigen levels and a history of prostate cancer exhibited rectoprostatic angle involvement and rectal wall thickening on MRI,with positron emission tomography/computed tomography PSMA confirming the prostatic origin of the metastatic *** third patient,an 80-year-old post-radical prostatectomy,presented with refractory *** revealed a neoplastic mass infiltrating the rectal *** all cases,MRI consistently showed stratified thickening,concentric signal changes,restricted diffusion,and contrast enhancement,which were essential for diagnosing secondary *** confirmed the prostatic origin of the neoplastic involvement in the *** Recognizing MRI findings of secondary RLP is essential for accurate diagnosis and management in prostate cancer patients.

关键词： Rectal linitis plastica Prostatic adenocarcinoma Signet ring cell carcinoma Metastatic spread Magnetic resonance imaging Concentric wall infiltration Case report

Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program

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Advances in Polar Science 2024年第1期35卷 132-140页

作者： Mariana A.JUÁRES AnahíM.SILVESTRO Brenda C.alfonso M.Mercedes SANTOS Departamento Biología de Predadores Tope Instituto Antártico Argentino(IAA)Buenos Aires B1650CSPArgentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Buenos Aires C1425FQBArgentina Laboratorios Anexos Facultad de Ciencias Naturales y MuseoUniversidad Nacional de La PlataLa Plata B1904AMAArgentina INEDES(CONICET-UNLu) Buenos Aires C1425FQBArgentina Facultad de Ciencias Naturales y Museo Universidad Nacional de La PlataLa Plata B1900FWAArgentina Instituto Antártico Argentino(IAA) Buenos Aires B1650CSPArgentina

In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/*** yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies ***,the magnitude of change was higher at Stranger Point than that in the remaining ***,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study ***,it displayed greater variability at Martin Point compared to the other two colonies under *** the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza ***,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point.

关键词： long-term monitoring Adélie penguin breeding pairs chicks crèched breeding success population trends

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Seventeenth-century Seville houses:a survey by the Alarife Juan De Legarra(1637)

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Built Heritage 2024年第2期8卷 13-32页

作者： Pilar Moya-Olmedo María Núñez-González fernando Vilaplana-Villajos Departamento de Ideación Gráfica Arquitectónica Escuela Técnica Superior de Arquitectura Universidad Politécnica de MadridAv.de Juan de Herrera 428040MadridSpain Departamento de Expresión Gráfica Arquitectónica Escuela Técnica Superior de Arquitectura Universidad de SevillaAv.de Reina Mercedes 2Seville41012Spain

Despite the wealth of preserved information,research on the domestic architecture of Seville has been *** of this historical data is available in survey books that were formally compiled in Seville from the Modern Age *** books had detailed descriptions and sometimes illustrations provided by surveyors who were commissioned by owners or *** intention of this study is to illustrate that the information contained in building surveys goes beyond simple descriptions or measurements often accompanied by *** are a comprehensive account that,even centuries later,help reconstruct the architecture,material culture and everyday life that no longer *** research contributes to the understanding of the domestic architectural history of Seville by focusing on one specific survey(a collection of drawings and a written description)extracted from the Hospital de las Cinco Llagas Collection,which is found in the Seville Provincial Council *** least one of the drawings and the written survey can be attributed to the Alarife(architect or master builder)Juan de Legarra,who signed them in *** research explores the architectural development of the city,offering fresh insights into its architecture,heritage,and *** supplements existing historical,visual,and written records derived from prior studies with a meticulously curated ***,it uses visualisation techniques to reconstruct buildings,augmenting the *** endeavour has yielded anticipated benefits,particularly in facilitating visual *** surveys have proven to be invaluable for historical inquiry,yielding unexpected insights through the thorough analysis of both written and graphic sources which serve as a basis for hypothetical construction plans due to their detailed ***,this study has contributed to enriching both historical and architectural *** incorporation of digital technologies into this architec

关键词： Historical documentation Survey Cultural heritage Virtual architecture Domestic architecture Archaeology

Microstructures and mechanical properties of laser-directed energy deposited CrCoNi medium-entropy alloy

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Rare Metals 2024年第7期43卷 3286-3300页

作者： Wen-Jie Zhao Chang-Yu Liu Peng-Cheng Che Zhi-Liang Ning Hong-Bo Fan Jian-Fei Sun Yong-Jiang Huang alfonso H.W.Ngan National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China Space Environment Simulation Research Infrastructure Harbin Institute of TechnologyHarbin 150001China Department of Mechanical Engineering The University of Hong KongHong Kong 999077China

The distinctive intrinsic heat treatment(IHT)originating from cyclic reheating in the laser-directed energy deposition(LDED) has attracted growing attention in recent *** this investigation,simulations and experimental characterizations were performed to examine the impact of IHT on the micros true ture and mechanical properties of LDED-fabricated CrCoNi medium-entropy alloy(MEA).The results show that the intensity of the IHT is proportional to the utilized laser energy density(LED).As the LED increased,significant dynamic recrystallization and grain refinement occurred within the alloy due to the enhanced intensity of ***,the high LED leads to severe hot cracking within the as-built MEA,resulting in inferior *** decreasing LED,the hot cracking was effectively ***,low LED weakened the intensity of IHT and consequently inhibited kinetic conditions of dynamic recrystallization,resulting in a heterogeneous grain structure characterized by multi-scale-sized *** structure provides significant hetero-deformation-induced hardening during plastic deformation,enabling the alloy to have a sustainable work-hardening *** expect that this work will have implications in taking full advantage of the unique IHT of the LDED process to fabricate ME As with excellent metallurgical quality and mechanical performance.

关键词： Intrinsic heat treatment Laser-directed energy deposition CrCoNi MEA Dynamic recrystallization Heterogeneous grain structure

Rotating effects on the photoionization cross-section of a 2D quantum ring

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Communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： Carlos Magno O Pereira Frankbelson dos S Azevedo Luís fernando C Pereira Edilberto O Silva Departamento de Física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. Solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. Specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoionization cross-section quantum ring rotating effect