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Machine learning based models for predicting compressive strength of geopolymer concrete

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1028-1049页

作者： quang-Huy le Duy-Hung NGUYEN Thanh SANG-TO Samir KHATIR Hoang le-MINH Amir H.GANDOMI Thanh CUONG-le Center for Engineering Application and Technology Solutions Ho Chi Minh City Open UniversityHo Chi Minh 700000Vietnam Institute of Civil Engineering Ho Chi Minh City University of TransportHo Chi Minh 700000Vietnam Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia

Recently,great attention has been paid to geopolymer concrete due to its advantageous mechanical and environmentally friendly *** effort has been made in experimental studies to advance the understanding of geopolymer concrete,in which compressive strength is one of the most important *** facilitate engineering work on the material,an efficient predicting model is *** this study,three machine learning(ML)-based models,namely deep neural network(DNN),K-nearest neighbors(KNN),and support vector machines(SVM),are developed for forecasting the compressive strength of the geopolymer concrete.A total of 375 experimental samples are collected from the literature to build a database for the development of the predicting models.A careful procedure for data preprocessing is implemented,by which outliers are examined and removed from the database and input variables are standardized before feeding to the fitting *** standard K-fold cross-validation approach is applied for evaluating the performance of the models so that overfitting status is well managed,thus the generalizability of the models is *** effectiveness of the models is assessed via statistical metrics including root mean squared error(RMSE),mean absolute error(MAE),correlation coefficient(R),and the recently proposed performance index(PI).The basic mean square error(MSE)is used as the loss function to be minimized during the model fitting *** three ML-based models are successfully developed for estimating the compressive strength,for which good correlations between the predicted and the true values are obtained for DNN,KNN,and *** numerical results suggest that the DNN model generally outperforms the other two models.

关键词： geopolymer concrete compressive strength prediction machine-learning based model deep neural network K-nearest neighbor support vector machines

High-Temperature Stability of Mg-1Al-12Y Alloy Containing LPSO Phase and Mechanism of Its Portevin-le Chatelier(PLC)Effect

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Acta Metallurgica Sinica(English letters) 2024年第6期37卷 982-998页

作者： Qian-Long Ren Shuai Yuan Shi-Yu luan Jin-Hui Wang Xiao-Wei Li Xiao-Yu Liu Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and FormingQinghai UniversityXining810016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China

In this study,the high-temperature stability and the generation mechanism of the Portevin-le Chatelier(PLC)effect in solid-solution Mg-1Al-12Y alloy with different heat treatment processes were investigated by adjusting the content of long-period stacking ordered(LPSO)*** was found that the content of LPSO phases in the alloys differed the most after heat treatment at 530℃for 16 h and 24 h,with values of 13.56%and 3.93%***,high-temperature tensile experiments were conducted on these two alloys at temperatures of 150℃,200℃,250℃,and 300℃.The results showed that both alloys exhibited the PLC effect at temperatures ranging from 150 to 250℃.However,at a temperature 300℃,only the alloy with a greater concentration of LPSO phases exhibited the PLC effect,whereas the alloy with a lower proportion of LPSO phases did not exhibit this ***,both alloys exhibited remarkable high-temperature stability,with the alloy containing a greater percentage of LPSO phases also demonstrating superior *** underlying mechanism for this phenomenon lies in the exceptional high-temperature stability exhibited by the second phase within the ***,the LPSO phase effectively obstructs the movement of dislocations,and it also undergoing kinking to facilitate plastic deformation of the *** results indicate that the PLC effect can be suppressed by reducing dislocation pile-up at grain boundaries,which leads to a decrease in alloy plasticity but an increase in *** presence of the PLC effect in the WA121 alloy is attributed to the abundant dispersed second phase within the alloy,which initially hinders the movement of dislocations,leading to an increase in stress,and subsequently releases the dislocations,allowing them to continue their movement and thereby reducing in stress.

关键词： Magnesium alloy Long-period stacking ordered(LPSO)phase Portevin-le Chatelier effect High temperature

Comparison of Treatment Efficacy of Different Number of Botulinum Toxin Type A Injection Sites for Crow's Feet Lines: A Single-Center Retrospective Clinical Study in Vietnam

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International Journal of Dermatology and Venereology 2024年第3期7卷 131-136页

作者： Nguyen quang M. le Thi M. Duong Phuc H. Vu Thai H. le Huu D. Department of Stem Cell Research and Application National Hospital of Dermatology and Venereology Hanoi 100000 Viet Nam Department of Healthcare Activity Direction National Hospital of Dermatology and Venereology Hanoi 100000 Viet Nam Department of Dermatology Hanoi Medical University Hanoi 100000 Viet Nam

Objective: Botulinum toxin type A is frequently used to treat crow's feet lines. However, the optimal dose and injection sites are still controversial. The objective of this study was to compare the efficacy of different botulinum toxin type A injection patterns for the treatment of crow's feet. Methods: This single-center, retrospective, clinical study was conducted at the National Hospital of Dermatology and Venereology from July 2020 to December 2020. Data on 60 patients with crow's feet were collected and divided into 2 groups (3- or 4-point intramuscular injection) according to the intramuscular injection technique the patients received. The treatment efficacy was assessed based on the changes in the Crow's Feet Grading Scale score at 1, 4, and 16 weeks after treatment. Repeated measures analysis of variance was used for the assessment of changes in scores over time between the two groups. Results: After treatment, the average Crow's Feet Grading Scale score was significantly decreased compared with the pretreatment score at all timepoints (1, 4, and 16 weeks) in both states (dynamic: For 3-point intramuscular injection technique, 1 week: 1.90 ± 0.71 vs. 2.97 ± 0.56; 4 weeks: 1.87 ± 0.68 vs. 2.97 ± 0.56; 16 weeks: 2.60 ± 0.67 vs. 2.97 ± 0.56. For 4-point intramuscular injection technique, 1 week: 1.73 ± 0.83 vs. 3.03 ± 0.49; 4 weeks: 1.73 ± 0.74 vs. 3.03 ± 0.49; 16 weeks: 2.57 ± 0.68 vs. 3.03 ± 0.49, all P < 0.001. and static: For 3-point intramuscular injection technique, 1 week: 1.20 ± 0.89 vs. 2.20 ± 0.85; 4 weeks: 1.20 ± 0.89 vs. 2.20 ± 0.85; 16 weeks: 1.87 ± 0.97 vs. 2.20 ± 0.85; For 4-point intramuscular injection technique, 1 week: 1.50 ± 0.86 vs. 2.30 ± 0.84; 4 weeks: 1.33 ± 0.84 vs. 2.30 ± 0.84; 16 weeks: 1.87 ± 0.97 vs. 2.30 ± 0.84. All P < 0.001). The average subjective patient-rated satisfaction scores after treatment were significantly higher in the 4-point injection group than in the 3-point injection group (P = 0.028). The adverse events were pos

关键词： botulinum toxin type A crow's feet lines dose injection site

Generating highly active oxide-phosphide heterostructure through interfacial engineering to break the energy scaling relation toward urea-assisted natural seawater electrolysis

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Journal of Energy Chemistry 2024年第10期97卷 687-699页

作者： Ngoc quang Tran Nam Hoang Vu Jianmin Yu Khanh Vy Pham Nguyen Thuy Tien Nguyen Tran Thuy-Kieu Truong Lishan Peng Thi Anh le Yoshiyuki Kawazoe Center for Innovative Materials and Architectures Vietnam National University Faculty of Materials Science and Technology University of Science Key Laboratory of Rare Earths Ganjiang Innovation Academy Chinese Academy of Sciences Department of Mechanical Engineering Hanbat National University (HBNU) School of Chemical Engineering-Hanoi University of Science and Technology New Industry Creation Hatchery Center Tohoku University

Urea-assisted natural seawater electrolysis is an emerging technology that is effective for grid-scale carbon-neutral hydrogen mass production yet *** scaling relations is an effective strategy to break through the bottleneck of natural seawater ***,by DFT calculation,we demonstrated that the interface boundaries between Ni2P and MoO2play an essential role in the selfrelaxation of the Ni-O interfacial bond,effectively modulating a coordination number of intermediates to control independently their adsorption-free energy,thus circumventing the adsorption-energy scaling *** this conceptual model,a well-defined 3D F-doped Ni2P-MoO2heterostructure microrod array was rationally designed via an interfacial engineering strategy toward urea-assisted natural seawater *** a result,the F-Ni2P-MoO2exhibits eminently active and durable bifunctional catalysts for both HER and OER in acid,alkaline,and alkaline sea water-based *** in-situ analysis,we found that a thin amorphous layer of NiOOH,which is evolved from the Ni2P during anodic reaction,is real catalytic active sites for the OER and UOR ***,such electrode-assembled urea-assisted natural seawater electrolyzer requires low voltages of 1.29 and 1.75 V to drive 10 and600 mA cm-2and demonstrates superior durability by operating continuously for 100 h at 100 mA cm-2,beyond commercial Pt/C || RuO2and most previous reports.

关键词： Break scaling relationships Doping Interfacial engineering Natural seawater splitting Urea electrolysis

Synthesis of hierarchically porous carbon materials by zinc salts-assisted carbonization of biomass and organic solid wastes

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Particuology 2024年第1期84卷 45-52页

作者： le-le Zhang lei Tong Yanwei Ding Wanqun Zhang Hai-Wei Liang Hefei National Research Center for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei230026China

Hierarchically porous carbons(HPCs)with multimodal pores have attracted considerable attention due to their unique physical and chemical properties and various application potentials in heterogeneous catalysis,environmental treatment,and energy storage and ***,we report a general and simple zinc salts-assisted method for the synthesis of HPCs with varied porosity and chemical func-tionalities by the direct carbonization of diverse biomass and *** the carbonization,zinc salts are thermally decomposed into nanoparticles that serve as in-situ templates to introduce nanopores in *** prepared HPCs exhibit high specific surface areas(up to 2432 m2 g-1),large pore volumes(up to 4.30 cm^(3)g^(-1)),and broad pore size ***,the zinc salts can be recovered and recycled,supporting the sustainable production of HPCs on large *** prepared HPCs-supported catalysts with atomically dispersed metal sites exhibit promising electrocatalytic performance for the oxygen reduction reaction.

关键词： Hierarchical porous carbon Zinc salts Biomass Wastes Electrocatalysis

Contrasting physical mechanisms of yellowfin tuna fluctuations between the western and eastern Indian Ocean

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Journal of Oceanology and Limnology 2024年第3期42卷 960-971页

作者： Peng LIAN le GAO Key Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Laboratory for Ocean Dynamics and Climate Laoshan LaboratoryQingdao 266061China

As an economically critical pelagic migratory species,yellowfin tuna(Thunnus albacores,YFT)is very sensible to physical and environmental conditions,such as sea surface temperature(SST),ocean heat content(OHC),and the mixed layer depth(MLD).We investigated the impact of SST,OHC,and MLD on fluctuations of YFT catch in the western/eastern Indian Ocean using the long time series of 63-year environmental and YFT *** found that the impact of SST on YFT was heavily overestimated in the past,and MLD plays a more critical role in the YFT catch *** the MLD deepens(>34.8 m),SST was more influential in predicting the catches of YFT than OHC in the western Indian Ocean,and OHC was more critical to YFT than SST in the eastern Indian ***,when the MLD shallows(<34.8 m),MLD was more vital to predict the catch per unit effort(CPUE)of YFT than SST/OHC in the *** 2000,there was an asynchronous pattern of YFT CPUE induced by higher frequency variations and ocean hiatus of SST/OHC signals in the western and eastern Indian Oceans *** impact of the subsurface hiatus may induce the decrease of YFT in the eastern Indian *** above findings clarified a non-stationary relationship between the environmental factors and catches of YFT and provided new insights into variations in YFT abundance.

关键词： yellowfin tuna Indian Ocean sea surface temperature(SST) ocean heat content(OHC) mixed layer depth(MLD) hiatus

Regulation of insect behavior by non-coding RNAs

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Science China(Life Sciences) 2024年第6期67卷 1106-1118页

作者： Jing He le Kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institutes of Life Sciences Chinese Academy of SciencesBeijing 100101China College of Life Science Hebei UniversityBaoding 071002China

The adaptation of insects to environments relies on a sophisticated set of behaviors controlled by molecular and physiological *** the past several decades,accumulating studies have unveiled the roles of non-coding RNAs(nc RNAs)in regulating insect *** RNAs assume particularly pivotal roles in the behavioral plasticity of insects by rapidly responding to environmental *** RNAs also contribute to the maintenance of homeostasis of insects by fine-tuning the expression of target ***,a comprehensive review of nc RNAs'roles in regulating insect behaviors has yet to be ***,we present the recent progress in our understanding of how nc RNAs regulate various insect behaviors,including flight and movement,social behavior,reproduction,learning and memory,and *** refine the intricate mechanisms by which nc RNAs modulate the function of neural,motor,reproductive,and other physiological systems,as well as gene expression in insects like fruit flies,social insects,locusts,and ***,we discuss potential avenues for future studies in nc RNA-mediated insect behaviors.

关键词： ncRNAs insect behavior plasticity fine-tuning environmental adaptation

Impacts of central-Pacific El Niño and physical drivers on eastern Pacific bigeye tuna

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Journal of Oceanology and Limnology 2024年第3期42卷 972-987页

Bigeye tuna Thunnus obesus is an important migratory species that forages deeply,and El Niño events highly influence its distribution in the eastern Pacific *** sea surface temperature is widely recognized as the main factor affecting bigeye tuna(BET)distribution during El Niño events,the roles of different types of El Niño and subsurface oceanic signals,such as ocean heat content and mixed layer depth,remain *** conducted A spatial-temporal analysis to investigate the relationship among BET distribution,El Niño events,and the underlying oceanic signals to address this knowledge *** used monthly purse seine fisheries data of BET in the eastern tropical Pacific Ocean(ETPO)from 1994 to 2012 and extracted the central-Pacific El Niño(CPEN)indices based on Niño 3 and Niño ***,we employed Explainable Artificial Intelligence(XAI)models to identify the main patterns and feature importance of the six environmental variables and used information flow analysis to determine the causality between the selected factors and BET ***,we analyzed Argo datasets to calculate the vertical,horizontal,and zonal mean temperature differences during CPEN and normal years to clarify the oceanic thermodynamic structure differences between the two types of *** findings reveal that BET distribution during the CPEN years is mainly driven by advection feedback of subsurface warmer thermal signals and vertically warmer habitats in the CPEN domain area,especially in high-yield fishing *** high frequency of CPEN events will likely lead to the westward shift of fisheries centers.

关键词： bigeye tuna central-Pacific El Niño(CPEN) ocean heat content Argo explainable artificial intelligence(XAI) information flow

A Comprehensive Survey of Recent Transformers in Image,Video and Diffusion Models

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Computers, Materials & Continua 2024年第7期80卷 37-60页

作者： Dinh Phu Cuong le Dong Wang Viet-Tuan le College of Computer Science and Electronic Engineering Hunan UniversityChangsha410082China Faculty of Information Technology Yersin University of Da LatDa Lat66100Vietnam Faculty of Information Technology Ho Chi Minh City Open UniversityHo Chi Minh City722000Vietnam

Transformer models have emerged as dominant networks for various tasks in computer vision compared to Convolutional Neural Networks(CNNs).The transformers demonstrate the ability to model long-range dependencies by utilizing a self-attention *** study aims to provide a comprehensive survey of recent transformerbased approaches in image and video applications,as well as diffusion *** begin by discussing existing surveys of vision transformers and comparing them to this ***,we review the main components of a vanilla transformer network,including the self-attention mechanism,feed-forward network,position encoding,*** the main part of this survey,we review recent transformer-based models in three categories:Transformer for downstream tasks,Vision Transformer for Generation,and Vision Transformer for *** also provide a comprehensive overview of recent transformer models for video tasks and diffusion *** compare the performance of various hierarchical transformer networks for multiple tasks on popular benchmark ***,we explore some future research directions to further improve the field.

关键词： Transformer vision transformer self-attention hierarchical transformer diffusion models