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Frontiers of Structural and Civil Engineering 2024年第6期18卷 899-917页

作者： Huong-Giang thi HOANG hai-van thi mai Hoang Long NGUYEN hai-Bang LY University of Transport Technology Hanoi 100000Vietnam

Complex modulus(G^(*))is one of the important criteria for asphalt classification according to AASHTO M320-10,and is often used to predict the linear viscoelastic behavior of asphalt *** addition,phase angle(φ)characterizes the deformation resilience of asphalt and is used to assess the ratio between the viscous and elastic *** is thus important to quickly and accurately estimate these two *** purpose of this investigation is to construct an extreme gradient boosting(XGB)model to predict G^(*)andφof graphene oxide(GO)modified asphaltat medium and high *** data sets are gathered from previously published experiments,consisting of 357 samples for G^(*)and 339 samples forφ,and the se are used to develop the XGB model using nine inputs representing theasphalt binder *** findings show that XGB is an excellent predictor of G^(*)andφof GO-modified asphalt,evaluated by the coefficient of determination R^(2)(R^(2)=0.990 and 0.9903 for G^(*)andφ,respectively)and root mean square error(RMSE=31.499 and 1.08 for G^(*)andφ,respectively).In addition,the model’s performance is compared with experimental results and five other machine learning(ML)models to highlight its *** the final step,the Shapley additive explanations(SHAP)value analysis is conducted to assess the impact of each input and the correlation between pairs of important features on asphalt’s two physical properties.

关键词： complex modulus phase angle graphene oxide asphalt extreme gradient boosting machine learning

Assessment of different machine learning techniques in predicting the compressive strength of self-compacting concrete

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Frontiers of Structural and Civil Engineering 2022年第7期16卷 928-945页

作者： van Quan TRAN hai-van thi mai Thuy-Anh NGUYEN hai-Bang LY Faculty of Civil Engineering University of Transport TechnologyHanoi 100000Vietnam

The compressive strength of self-compacting concrete(SCC)needs to be determined during the construction design *** paper shows that the compressive strength of SCC(CS of SCC)can be successfully predicted from mix design and curing age by a machine learning(ML)technique named the Extreme Gradient Boosting(XGB)algorithm,including non-hybrid and hybrid *** ML techniques,such as Linear regression(LR),K-Nearest Neighbors(KNN),Support Vector Machine(SVM),Decision Trees(DTR),Random Forest(RF),Gradient Boosting(GB),and Artificial Neural Network using two training algorithms LBFGS and SGD(denoted as ANN_LBFGS and ANN_SGD),are also compared with the XGB ***,the hybrid models of eight ML techniques and Particle Swarm Optimization(PSO)are constructed to highlight the reliability and accuracy of SCC compressive strength prediction by the XGB_PSO hybrid *** highest number of SCC samples available in the literature is collected for building the ML *** with previously published works’performance,the proposed XGB method,both hybrid and non-hybrid models,is the most reliable and robust of the examined techniques,and is more accurate than existing ML methods(R2=0.9644,RMSE=4.7801,and MAE=3.4832).Therefore,the XGB model can be used as a practical tool for engineers in predicting the CS of SCC.

关键词： compressive strength self-compacting concrete machine learning techniques particle swarm optimization extreme gradient boosting

Optimization of machine learning models for predicting the compressive strength of fiber-reinforced self-compacting concrete

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结构与土木工程前沿:英文版 2023年第2期17卷 284-305页

作者： hai-van thi mai May Huu NGUYEN Son Hoang TRINH hai-Bang LY Civil Engineering Department University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

Fiber-reinforced self-compacting concrete(FRSCC)is a typical construction material,and its compressive strength(CS)is a critical mechanical property that must be adequately *** the machine learning(ML)approach to estimating the CS of FRSCC,the current research gaps include the limitations of samples in databases,the applicability constraints of models owing to limited mixture components,and the possibility of applying recently proposed *** study developed different ML models for predicting the CS of FRSCC to address these *** neural network,random forest,and categorical gradient boosting(CatBoost)models were optimized to derive the best predictive model with the aid of a 10-fold cross-validation technique.A database of 381 samples was created,representing the most significant FRSCC dataset compared with previous studies,and it was used for model *** findings indicated that CatBoost outperformed the other two models with excellent predictive abilities(root mean square error of 2.639 MPa,mean absolute error of 1.669 MPa,and coefficient of determination of 0.986 for the test dataset).Finally,a sensitivity analysis using a partial dependence plot was conducted to obtain a thorough understanding of the effect of each input variable on the predicted CS of *** results showed that the cement content,testing age,and superplasticizer content are the most critical factors affecting the CS.

关键词： compressive strength self-compacting concrete artificial neural network decision tree CatBoost

High-temperature corrosion of sintered RE_(2)Si_(2)O_(7)(RE=Yb and Ho)environmental barrier coating materials by volcanic ash

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1628-1638页

作者： Ayahisa Okawa Son Thanh Nguyen Tadachika Nakayama thi-mai-Dung Do Hisayuki Suematsu Shu Yin Takuya Hasegawa Tsuneo Suzuki Takashi Goto Koichi Niihara Institute of Multidisciplinary Research for Advanced Materials Tohoku UniversitySendai 980-8577Japan Department of Creative Engineering National Institute of TechnologyKushiro 084-0916Japan Extreme Energy-Density Research Institute Nagaoka University of TechnologyNagaoka 940-2188Japan Advanced Institute for Materials Research(WPI-AIMR) Tohoku UniversitySendai 980-8577Japan

Rare-earth silicates are promising environmental barrier coatings(EBCs)that can protect SiC_(f)/Si C_(m)substrates in next-genera tion gas turbine ***,RE_(2)Si_(2)O_(7)(RE=Yb and Ho)shows potential as an EBC due to its coefficient of thermal expansion(CTE)compatible with substrates and high resistance to water vapor *** target operating temperature for next-generation tur bine blades is 1400°*** is inevitable during adhesion to molten volcanic ash,and thus,understanding the corrosion behavior o the material is crucial to its *** study investigates the high-temperature corrosion behavior of sintered RE_(2)Si_(2)O_(7)(RE=Yb and Ho).Samples were prepared using a solid-state reaction and hot-press *** were then exposed to volcanic ash at 1400°C for 224,and 48 *** 48 h of exposure,volcanic ash did not react with Yb_(2)Si_(2)O_(7)but penetrated its interior,causing *** Ho_(2)Si_(2)O_(7)was partially dissolved in the molten volcanic ash,forming a reaction zone that prevented volcanic ash melts from penetrating the *** increasing heat treatment time,the reaction zone expanded,and the thickness of the acicular apatite grains increased The Ca:Si ratios in the residual volcanic ash were mostly unchanged for Yb_(2)Si_(2)O_(7)but decreased considerably over time for Ho_(2)Si_(2)O_(7).Th Ca in volcanic ash was consumed and formed apatite,indicating that RE^(3+)ions with large ionic radii(Ho>Yb)easily precipitated apatit from the volcanic ash.

关键词： environmental barrier coating volcanic ash rare-earth disilicate corrosion

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03期

作者： Quang Minh Nguyen Le thi mai Phuc Hieu Duong Vu Thai Ha Le Huu Doanh Department of Stem Cell Research and Application National Hospital of Dermatology and Venereology Hanoi Vietnam Department of Healthcare Activity Direction National Hospital of Dermatology and Venereology Hanoi Vietnam Department of Dermatology Hanoi Medical University Hanoi Vietnam

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 ***: 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 ***: 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 ± 0.71vs. 2.97 ± 0.56; 4 weeks: 1.87 ± 0.68vs. 2.97 ± 0.56; 16 weeks: 2.60 ± 0.67vs. 2.97 ± 0.56. For 4-point intramuscular injection technique, 1 week: 1.73 ± 0.83vs. 3.03 ± 0.49; 4 weeks: 1.73 ± 0.74vs. 3.03 ± 0.49; 16 weeks: 2.57 ± 0.68vs. 3.03 ± 0.49, allP < 0.001. and static: For 3-point intramuscular injection technique, 1 week: 1.20 ± 0.89vs. 2.20 ± 0.85; 4 weeks:1.20 ± 0.89vs. 2.20 ± 0.85; 16 weeks: 1.87 ± 0.97vs. 2.20 ± 0.85; For 4-point intramuscular injection technique, 1 week: 1.50 ± 0.86vs. 2.30 ± 0.84; 4 weeks: 1.33 ± 0.84vs. 2.30 ± 0.84; 16 weeks: 1.87 ± 0.97vs. 2.30 ± 0.84. AllP < 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 post-injection bruisi

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

Effect of heating time on structural,morphology,optical,and photocatalytic properties of g-C3N4 nanosheets

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Chinese Physics B 2020年第5期29卷 504-508页

作者： Nguyen Manh Hung Le thi mai Oanh Lam thi Hang Pham Do Chung Pham thi Duyen Dao Viet Thang Nguyen van Minh Center for Nano Science and Technology Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi100000Vietnam Department of Physics Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi100000Vietnam Faculty of Basic Sciences Hanoi University of Natural Resources and Environment41A Phu Dien RoadNorth Tu LiemHanoi100000Vietnam Hanoi University of Mining and Geology Duc Thang wardNorth Tu Liem DistrictHanoi100000Vietnam Military science Academy 322 Le Trong Tan streetDinh CongHoang MaiHanoi100000Vietnam

Effect of heating time on the structural,morphology,optical,and photocatalytic properties of graphitic carbon nitride(g-C3N4)nanosheets prepared at 550℃in Ar atmosphere is *** investigations are carried out by using x-ray diffraction(XRD),scanning electron microscopy(SEM),Fourier-transform infrared spectroscopy(FTIR),UV-vis absorption,and photoluminescence(PL).At a heating temperature of 550℃,g-C3N4 nanocrystals are formed after 0.5 h and become more orderly as the heating time *** surface area of the g-C3N4 nanosheets significantly increases as the preparation time *** g-C3N4 prepared in 2.5 h shows the highest photocatalytic performance,decomposing completely 10 ppm RhB solution under xenon lamp irradiation for 2.0 h.

关键词： nanosheets photocatalytic heating time Ar atmosphere

Invariant Lighting Hand Posture Classification

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Invariant Lighting Hand Posture Classification

Ziwan-Taoren herb pair can exert an therapeutical effect in primary Sjogren’s syndrome through inhibiting the TLR/NF-κB pathway

The 2010 IEEE International Conference on Progress in Informatics and Computing

作者： thi-Thanh-hai Tran thi-Thanh-mai Nguyen MICA International Research Center Hanoi University of Science and Technology VietNam

ISBN: (纸本)9781424467860

＜正＞Hand posture classification is a key problem for many human computer interaction ***,this is not a simple *** this paper,we propose to decompose the hand posture classification problem into 2 *** the first step,we detect skin regions using a very fast algorithm of color segmentation based on thresholding *** segmentation is robust to lighting condition thank to a step of color normalization using neural *** the second step, each skin region will be classified into one of hand posture class using Cascaded Adaboost *** contributions of this paper are:（i） By applying a step of color normalization,the posture classification rate is significantly improved under varying lighting condition;（ii） The cascaded Adaboost technique has been studied for the problem of face detection（2 classes）.In this paper, it will be studied and evaluated in more detail in a problem of classification of hand postures（multi-classes）.

关键词： Hand posture classification Cascaced Adaboost Color normalization Neural network Lighting invariance

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Traditional Medicine Research 2024年第8期9卷 11-22页

作者： Kuok-Tong Lei Yun-Xia Wu Yun Lu Zi-Shan Wang thi-Huong Nguyen Qiu-Ying Cai Wen Zhu Yue Wang First Clinical Medical College Nanjing University of Chinese MedicineNanjing 210000China Faculty of Traditional Medicine Phenikaa UniversityHa Noi 100803Vietnam Department of Rheumatology and Immunology Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210000China

Background:Ziwan and Taoren(ZT)is a classic medicine pair in the formula of mai Dong Di Shao Decoction,has been used to treat primary Sjogren’s syndrome(pSS)for more than 20 *** its action mechanism is still *** study is aimed to reveal the potential mechanism of ZT treated pSS and discover its active compounds of ZT and therapeutic target for ***:Firstly,the potential pathways of ZT for pSS treatment were predicted through network pharmacology and GO and KEGG enrichment ***,the inter-structural relationships between active compounds of ZT and target proteins were visualized using molecular docking ***,efficacy and mechanism were conducted through in vivo experiments,such as water intake,spleen index,hematoxylin-eosin staining pathological changes,ELISA,Western Blot analysis,and immunofluorescence ***:Nine active compounds were extracted from network pharmacology,including quercitrin,luteolin,kaempferol,β-sitosterol,isorhamnetin,galangin,hederagenin,diosmetin and gibberellin *** disease targets were identified:RELA,TP53,AKT1,interleukin(IL)6,MAPK1,ESR1,IL10;with RELA being the most core *** and GO enrichment analysis indicated that ZT may act through the TLR/NF-κB/RELA inflammatory mechanism *** results of molecular docking showed that ZT’s active compounds bind well to the RELA(p65)*** vivo results demonstrated that a high dose of ZT significantly improved water intake and reduced lymphocytes infiltration in submandibular gland pathology in NOD *** expression content of AQP5 and vasoactive intestinal peptide in the submaxillary gland was significantly increased,while levels of inflammatory factors such as tumor necrosis factor-α,IL-6,and IL-1βalong with protein expressions including toll-like receptor4,p-p65 and p-IKKα/βin NF-κB pathway were ***:The ZT treatment exhibits a promising efficacy in mitigating dryness symptoms of pSS,potentially attr

关键词： traditional Chinese medicine primary Sjogren’s syndrome NF-κB RELA

New Results on Stability and Stabilization of Delayed Caputo Fractional Order Systems with Convex Polytopic Uncertainties

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Journal of Systems Science & Complexity 2020年第3期33卷 563-583页

作者： DINH Cong Huong mai Viet Thuan DUONG thi Hong Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh CityVietnam Department of Mathematics and Informatics Thainguyen University of SciencesThainguyenVietnam

In this paper,the problems of robust stability and stabilization,for the first time,are studied for delayed fractional-order linear systems with convex polytopic *** authors derive some sufficient conditions for the problems based on linear matrix inequality technique combined with fractional Razumikhin stability *** the results are obtained in terms of linear matrix inequalities that are numerically *** proposed results are quite general and improve those given in the literature since many factors,such as discrete and distributed delays,convex polytopic uncertainties,global stability and stabilizability,are *** examples and simulation results are given to illustrate the effectiveness of the effectiveness of our results.

关键词： Convex polytopic uncertainty delayed caputo fractional-order systems fractional Razumikhin theorem linear matrix inequality robust stability robust stabilization

New Results on H_(∞) Control for Nonlinear Conformable Fractional Order Systems

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Journal of Systems Science & Complexity 2021年第1期34卷 140-156页

作者： mai Viet Thuan NGUYEN thi Huyen Thu NGUYEN Huu Sau NGUYEN thi Thanh Huyen Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of General Science Hanoi University of Natural Resources and EnvironmentHanoiVietnam Faculty of Fundamental Science Hanoi University of IndustryHa NoiVietnam Department of Mathematics and Informatics Thainguyen University of SciencesThainguyenVietnam

this paper deals with H_(∞) control problem for nonlinear conformable fractional order systems. The authors first derive new sufficient condition for exponential stability of nonlinear conformable fractional order systems based on Lyapunov-like function method for conformable fractional order systems and linear matrix inequalities(LMIs) approach. Then, by introducing a new concepts of H_(∞) control problem for nonlinear conformable fractional order systems, the authors study H_(∞) performance analysis and H_(∞) state feedback controller design problems for the considered systems. In terms of LMIs, a sufficient condition is proposed to ensure the nonlinear conformable fractional order systems are not only exponentially stable, but also satisfy H_(∞) performance γ. An explicit expression for state feedback controllers is also designed to make the closed-loop system is exponentially stable with H_∞performance γ. Finally, numerical examples are given to illustrate the validity and effectiveness of the proposed results.

关键词： Conformable fractional-order H_(∞)control problems H_(∞)performance analysis linear matrix inequalities nonlinear systems