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Multi-layer perceptron-based data-driven multiscale modelling of granular materials with a novel Frobenius norm-based internal variable

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Journal of Rock Mechanics and Geotechnical engineering 2024年第6期16卷 2198-2218页

作者： Mengqi Wang y.T.Feng Shaoheng Guan Tongming Qu Zienkiewicz Centre for Computational engineering Faculty of Science and EngineeringSwansea UniversitySwanseaWalesSA18EPUK Institute of Theoretical and Computational Physics Graz University of TechnologyGraz8010Austria Department of Civil and environmental engineering Hong Kong University of Science and TechnologyClearwater BayKowloonHong KongChina

One objective of developing machine learning(ML)-based material models is to integrate them with well-established numerical methods to solve boundary value problems(BVPs).In the family of ML models,recurrent neural networks(RNNs)have been extensively applied to capture history-dependent constitutive responses of granular materials,but these multiple-step-based neural networks are neither sufficiently efficient nor aligned with the standard finite element method(FeM).Single-step-based neural networks like the multi-layer perceptron(MLP)are an alternative to bypass the above issues but have to introduce some internal variables to encode complex loading *** this work,one novel Frobenius norm-based internal variable,together with the Fourier layer and residual architectureenhanced MLP model,is crafted to replicate the history-dependent constitutive features of representative volume element(RVe)for granular *** obtained ML models are then seamlessly embedded into the FeM to solve the BVP of a biaxial compression case and a rigid strip footing *** obtained solutions are comparable to results from the FeM-DeM multiscale modelling but achieve significantly improved *** results demonstrate the applicability of the proposed internal variable in enabling MLP to capture highly nonlinear constitutive responses of granular materials.

关键词： Granular materials History-dependence Multi-layer perceptron(MLP) Discrete element method FeM-DeM Machine learning

Multi-population particle swarm optimization algorithm for automatic design of steel frames

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Frontiers of Structural and Civil engineering 2024年第1期18卷 89-103页

作者： Wenchen SHAN Jiepeng LIU yao DING y.Frank CHeN Junwen ZHOU Institute of Smart City and Intelligent Transportation Southwest Jiaotong UniversityChengdu 610000China School of Civil engineering Chongqing UniversityChongqing 400045China Department of Civil engineering the Pennsylvania State UniversityMiddletownPA 17057USA

Steel structures are widely used;however,their traditional design method is a trial-and-error procedure which is neither efficient nor cost ***,a multi-population particle swarm optimization(MPPSO)algorithm is developed to optimize the weight of steel frames according to standard design *** are made to improve the algorithm performances including the constraint-based strategy,piecewise mean learning strategy and multi-population cooperative *** proposed method is tested against the representative frame taken from American standards and against other steel frames matching Chinese design *** related parameter influences on optimization results are *** the representative frame,MPPSO can achieve greater efficiency through reduction of the number of analyses by more than 65% and can obtain frame with the weight for at least 2.4%lighter.A similar trend can also be observed in cases subjected to Chinese design *** addition,a migration interval of 1 and the number of populations as 5 are recommended to obtain better MPPSO *** purpose of the study is to propose a method with high efficiency and robustness that is not confined to structural scales and design *** aims to provide a reference for automatic structural optimization design problems even with dimensional *** proposed method can be easily generalized to the optimization problem of other structural systems.

关键词： steel frame multi-population particle swarm optimization automatic structural optimization design

Artificial optoelectronic synapse based on spatiotemporal irradiation to source-sharing circuitry of synaptic phototransistors

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InfoMat 2024年第2期6卷 131-141页

作者： Seungho Song Changsoon Choi Jongtae Ahn je-Jun Lee Jisu Jang Byoung-Soo yu Jung Pyo Hong yong-Sang Ryu yong-Hoon Kim Do Kyung Hwang Center for Opto-electronic Materials and Devices Post-Silicon Semiconductor InstituteKorea Institute of Science and Technology(KIST)SeoulRepublic of Korea School of Advanced Materials Science and engineering Sungkyunkwan UniversitySuwonRepublic of Korea Center for Spintronics Post-Silicon Semiconductor InstituteKorea Institute of Science and Technology(KIST)SeoulRepublic of Korea Division of Nanoscience&Technology KIST SchoolUniversity of Science and Technology(UST)SeoulRepublic of Korea School of Biomedical engineering Korea UniversitySeoulRepublic of Korea KU-KIST Graduate School of Converging Science and Technology Korea UniversitySeoulRepublic of Korea

To overcome the intrinsic inefficiency of the von Neumann architecture,neuromorphic devices that perform analog vector–matrix multiplication have been highlighted for achieving power-and time-efficient data *** particular,artificial synapses,of which conductance should be programmed to represent the synaptic weights of the artificial neural network,have been intensively researched to realize neuromorphic ***,inspired by excitatory and inhibitory synapses,we develop an artificial optoelectronic synapse that shows both potentiation and depression characteristics triggered only by optical *** design of the artificial optoelectronic synapse,in which excitatory and inhibitory synaptic phototransistors are serially connected,enables these characteristics by spatiotemporally irradiating the phototransistor channels with optical ***,a negative synaptic weight can be realized without the need for electronic components such as *** such attributes,the artificial optoelectronic synapse is demonstrated to classify three digits with a high recognition rate(98.3%)and perform image preprocessing via analog vector-matrix multiplication.

关键词： amorphous oxide semiconductor analog processing artificial synapse neuromorphic optoelectronics

CLASSIFICATIONS OF DUPIN HyPeRSURFACeS IN LIe SPHeRe GeOMeTRy

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Acta Mathematica Scientia 2024年第1期44卷 1-36页

作者： Thomas e.CeCIL Department of Mathematics and Computer Science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in S^(n)(or R^(n))that have been obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of S^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： R Gharaei e Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and Guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the Guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations

Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： J.e.Hirsch Department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

Subnormal Serum Liver enzyme Levels:A Review of Pathophysiology and Clinical Significance

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Journal of Clinical and Translational Hepatology 2024年第4期12卷 428-435页

作者： elham M.youssef George y.Wu Biochemistry Department National Research CenterCairoEgypt Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

Subnormal levels of liver enzymes,below the lower limit of normal on local laboratory reports,can be useful *** instance,subnormal levels of aminotransferases can be observed in vitamin B6 deficiency and chronic kidney *** alkaline phosphatase levels may indicate the presence of hypophosphatasia,Wilson's disease,deficiencies of divalent ions,or *** levels of gamma glutamyl transferase may be seen in cases of acute intrahepatic cholestasis,the use of certain medications,and in bone ***,subnormal levels of 5'-nucleotidase have been reported in lead poisoning and nonspherocytic hemolytic *** aim of this review is to bring attention to the fact that subnormal levels of these enzymes should not be ignored as they may indicate pathological conditions and provide a means of early diagnosis.

关键词： Transaminases Vitamin B6 Celiac disease Renal insufficiency Hepatolenticular Degeneration Crohn disease Malnutrition Clofibrate Bone diseases Lead poisoning Anemia Hemolytic

Factors influencing farmers’adoption of solar water-pumping systems in Gujarat

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Clean energy 2024年第3期8卷 157-165页

作者： M Sathish Kumar y.A.Lad R.S.Pundir International Agribusiness Management Institute Anand Agricultural UniversityAnand388110GujaratIndia Department of HRD&PM International Agribusiness Management InstituteAnand Agricultural UniversityAnand388110GujaratIndia Department of Agribusiness economics and Policies International Agribusiness Management InstituteAnand Agricultural UniversityAnand388110GujaratIndia

Agriculture has played an important role in the growth of the Indian *** and electricity are essential inputs for agriculture *** produces the third-largest amount of electricity in the world,behind China and the *** an incentive to increase production,most states provide free electricity to *** electricity has decreased groundwater levels and increased electricity *** objective of this study was to find out the factors that influenced farmers to adopt a solar water-pumping system in *** samples were randomly *** study examined the entire state of *** hundred and fifty farmers who adopted solar water-pumping systems were interviewed,including 50 banana farmers,50 cotton farmers and 50 groundnut *** data were collected through an *** adoption of solar water-pumping systems by farmers was identified using factor *** software was used to analyse the data *** this study,only two factors contributed to the variance of 59.469%.The adoption of solar water pumps by farmers was influenced by government policy and economic *** economic benefit variance of 33.20%was found,while a government policy variance was 26.27%.A solar water-pumping system has low initial costs,flexible credit policies motivate adoption,solar water-pumping systems can save electricity,and maintenance and repair costs are *** policy that includes solar water-pumping systems is motivated by awareness,subsidies for adoption and a fair price to sell energy *** are recommended to adopt a solar water-pumping system in conjunction with a drip irrigation system to receive additional *** successful scheme will be recommended to other states in India for implementation.

关键词： solar water-pumping system factor analysis banana cotton groundnut famers

etiologies of Splenic Venous Hypertension:A Review

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Journal of Clinical and Translational Hepatology 2024年第6期12卷 594-606页

作者： Jasmine Tidwell Bianca Thakkar George y.Wu Department of Medicine University of Connecticut Health CenterFarmingtonCTUSA Division of Gastroenterology-Hepatology University of Connecticut Health CenterFarmingtonCTUSA

Splenic venous hypertension or left-sided portal hypertension is a rare condition caused by an obstruction of the splenic ***,it presents with upper gastrointestinal bleeding in the absence of liver *** can be classified based on the mechanism of development of splenic vein hypertension:compression,stenosis,inflammation,thrombosis,and surgically decreased splenic venous *** is established by various imaging modalities and should be suspected in patients with gastric varices in the absence of esophageal varices,splenomegaly,or *** management and prognosis vary depending on the underlying etiology but generally involve reducing splenic venous *** aim of this review was to summarize the etiologies of splenic venous hypertension according to the mechanism of development.

关键词： Splenic venous hypertension Left-sided portal hypertension Sinistral portal hypertension Splenic vein thrombosis Gastric varices Hematemesis Upper gastrointestinal bleeding