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Some Strong Laws of Large Numbers for Blockwise Martingale Difference Sequences in Martingale Type p Banach Spaces

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Acta Mathematica Sinica,English Series 2012年第7期28卷 1385-1400页

作者： Andrew ROSALSKY le van thanh Department of Statistics University of Florida Department of Mathematics Vinh University

For a blockwise martingale difference sequence of random elements {Vn, n ≥ 1} taking values in a real separable martingale type p （1 ≤ p ≤ 2） Banach space, conditions are provided for strong laws of large numbers of the form limn→∞ Vi/gn = 0 almost surely to hold where the constants gn ↑∞. A result of Hall and Heyde [Martingale Limit Theory and Its Application, Academic Press, New York, 1980, p. 36] which was obtained for sequences of random variables is extended to a martingale type p （1〈 p ≤2） Banach space setting and to hold with a Marcinkiewicz-Zygmund type normalization. Illustrative examples and counterexamples are provided.

关键词： Sequence of Banach space valued random elements blockwise martingale difference sequence strong law of large numbers almost sure convergence martingale type p Banach space

On the Laws of Large Numbers for Double Arrays of Independent Random Elements in Banach Spaces

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Acta Mathematica Sinica,English Series 2014年第8期30卷 1353-1364页

作者： Andrew ROSALSKY le van thanh Nguyen Thi THUY Department of Statistics University of FloridaGainesville Department of Mathematics Vinh University

For a double array of independent random elements {Vmn,m ≥ 1,n ≥ 1} in a real separable Banach space,conditions are provided under which the weak and strong laws of large numbers for the double sums mi=1 nj=1Vij,m ≥ 1,n ≥ 1 are *** the identically distributed and the nonidentically distributed cases are *** the main theorems,no assumptions are made concerning the geometry of the underlying Banach *** theorems are applied to obtain Kolmogorov,Brunk–Chung,and Marcinkiewicz–Zygmund type strong laws of large numbers for double sums in Rademacher type p（1 ≤ p ≤ 2） Banach spaces.

关键词： Real separable Banach space double array of independent random elements strong and weak laws of large numbers almost sure convergence convergence in probability Rademacher type p Banach space

Dynamic response of honeycomb-FGS shells subjected to the dynamic loading using non-polynomial higher-order IGA

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Defence Technology（防务技术） 2024年第7期37卷 149-161页

作者： Pham Binh le Trung-thanh Tran Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam

The main goal of this study is to use higher-order isogeometric analysis(IGA)to study the dynamic response of sandwich shells with an auxetic honeycomb core and two different functionally graded materials(FGM)skin layers(namely honeycomb-FGS shells)subjected to dynamic ***'s non-polynomial higher-order shear deformation theory(HSDT)is used due to its simplicity and *** governing equation is derived from Hamilton's *** verifying the present approach,the effect of input parameters on the dynamic response of honeycomb-FGS shells is carried out in detail.

关键词： IGA Elastic foundation Dynamic response FGM Auxetic honeycomb Shell

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

Combined transarterial chemoembolization and stereotactic body radiation therapy as a bridge therapy to liver transplant for hepatocellular carcinoma

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Hepatoma Research 2020年第8期6卷 36-45页

作者： Bui Quang Bieu Nguyen Dinh Chau Nguyen Xuan Kien le van thanh Vu van Quang Thai Doan Ky Nguyen Tien Thinh Mai Hong Bang Department of Radiation Oncology and Radiosurgery Military Central Hospital 108Hanoi 100000Vietnam Department of Hepatobiliary and Pancreatic Surgery Military Central Hospital 108Hanoi 100000Vietnam Department of Gastroenterology and Hepatobiliary Military Central Hospital 108Hanoi 100000Vietnam.

Liver transplant(LT)is the curative treatment for patients with hepatocellular carcinoma(HCC).Bridge therapies are local treatments given to patients on the LT waitlist,to prevent tumor progression and to reduce the dropout *** presentation:We reported a 40-year-old man diagnosed with Barcenola-Clinic Liver Cancer BCLC intermediate stage HCC and Child-Pugh A5 hepatitis B virus cirrhosis who underwent combined bridge therapies to ***,the patient received transarterial chemoembolization(TACE)for two times and showed a partial *** he underwent stereotactic body radiation therapy(SBRT)with a total dose of 45 Gy in 3 *** months later,the tumor size and serum protein induced by Vitamin K absence or antagonists-II,alpha fetoprotein levels decreased *** June 2019 a suitable donor was found and his LT was successfully ***:We propose that a combination of TACE and SBRT was feasible as bridge therapy for HCC patients on the LT waitlist.

关键词： Transarterial chemoembolization stereotactic body radiation therapy bridge therapy hepatocellular carcinoma liver transplant

软木塞基碳量子点的水热合成及其生物相融荧光成像应用

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新型炭材料 2022年第3期37卷 595-602页

作者： Quang Ngo Khoa Hieu Nguyen Ngoc Bao Vo van Quoc Phuoc Vo Thi Ngoc le Xuan Diem Doc Luong Quang Tri Nguyen Minh Son le Vu Truong Son le van thanh Ha Che Thi Cam University of Sciences Hue University77 Nguyen HueHueVietnam Faculty of Environmental and Natural Sciences Duy Tan UniversityDa Nang550000Vietnam Institute for Research and Training in Medicine Biology and PharmacyDuy Tan UniversityDa Nang550000Vietnam University of Agriculture and Forestry Hue University102 Phung HungHueVietnam University of Science and Education The University of Da Nang459 Ton Duc ThangLien ChieuDa NangVietnam

以废弃酒瓶软木塞为原料,采用低成本、简单的水热方法合成碳量子点。通过TEM、FTIR、Raman、UV-Vis、PL光谱对碳量子点的结构和光学性能进行分析表征。结果表明,碳量子点的平均直径为6.2±2.7 nm,PL激发谱和碳量子点表面的官能团有关。... 详细信息

以废弃酒瓶软木塞为原料,采用低成本、简单的水热方法合成碳量子点。通过TEM、FTIR、Raman、UV-Vis、PL光谱对碳量子点的结构和光学性能进行分析表征。结果表明,碳量子点的平均直径为6.2±2.7 nm,PL激发谱和碳量子点表面的官能团有关。用硫酸奎宁作为参考,碳量子点的量子效率为1.54%。将获得的碳量子点应用在骨髓间充质干细胞的细胞生物成像上,发现用碳量子点处理后,骨髓间充质干细胞分别在320~380 nm、450~490 nm和450~490 nm范围显示绿色、黄色和红色荧光,表明了碳量子点在荧光成像领域具有潜在的应用价值。

关键词：碳点水热合成荧光荧光图像废酒瓶塞

An efficient improved Gradient Boosting for strain prediction in Near-Surface Mounted fiber-reinforced polymer strengthened reinforced concrete beam

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1148-1168页

作者： Abdelwahhab KHATIR Roberto CAPOZUCCA Samir KHATIR Erica MAGAGNINI Brahim BENAISSA thanh CUONG-le Structural Section DICEA Polytechnic University of MarcheAncona 60131Italy Centre for Engineering Application&Technology Solutions Ho Chi Minh City Open UniversityHo Chi Minh City 70000Vietnam Design Engineering Laboratory Toyota Technological InstituteNagoya 468-8511Japan

The Near-Surface Mounted(NSM)strengthening technique has emerged as a promising alternative to traditional strengthening methods in recent *** the past two decades,researchers have extensively studied its potential,advantages,and applications,as well as related parameters,aiming at optimization of construction ***,there is still a need to explore further,both from a static perspective,which involves accounting for the nonconservation of the contact section resulting from the bond-slip effect between fiber-reinforced polymer(FRP)rods and resin and is typically neglected by existing analytical models,as well as from a dynamic standpoint,which involves studying the trends of vibration frequencies to understand the effects of various forms of damage and the efficiency of *** address this gap in knowledge,this research involves static and dynamic tests on simply supported reinforced concrete(RC)beams using rods of NSM carbon fiber reinforced polymer(CFRP)and glass fiber reinforced polymer(GFRP).The main objective is to examine the effects of various strengthening *** research conducts bending tests with loading cycles until failure,and it helps to define the behavior of beam specimens under various damage degrees,including concrete *** analysis by free vibration testing enables tracking of the effectiveness of the reinforcement at various damage levels at each stage of the loading *** addition,application of Particle Swarm Optimization(PSO)and Genetic Algorithm(GA)is proposed to optimize Gradient Boosting(GB)training performance for concrete strain prediction in NSM-FRP *** GB using Particle Swarm Optimization(GBPSO)and GB using Genetic Algorithm(GBGA)systems were trained using an experimental data set,where the input data was a static applied load and the output data was the consequent *** models of GBPSO and GBGA have been shown to provide highly accurate results for predicting *** model

关键词： NSM technique fiber-reinforced polymer rods static and dynamic analysis GB PSO GA finite element analysis

Prevalence and risk factors associated with long COVID symptoms in children and adolescents in a southern province of Vietnam

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Asian Pacific Journal of Tropical Medicine 2024年第3期17卷 119-128,I0001,I0002页

作者： Huynh Ngoc Linh Nguyen The Tan le Thi Minh Thu Nguyen Tu Loan Nguyen Thi To Uyen le thanh Thao Trang Truong thanh Nam Doan Hoang Phu Faculty of Medicine Ca Mau Medical CollegeCa Mau 98000Vietnam Ca Mau Obstetrics and Pediatrics Hospital Ca Mau 98000Vietnam Faculty of Basic Science and Public Health Dong Thap Medical CollegeDong Thap 81000Vietnam Graduate University of Sciences and Technology Vietnam Academy of Science and TechnologyHa Noi 10000Vietnam Community Public Health Research Program School of Public HealthWalailak UniversityNakhon Si Thammarat 80160Thailand Faculty Public Health Can Tho University of Medicine and PharmacyCan Tho City 94000Vietnam Doctoral Program in Health Sciences College of Graduate StudiesWalailak UniversityNakhon Si Thammarat 80160Thailand

Objective:To investigate the prevalence and risk factors associated with long COVID symptoms among children and adolescents who have recovered from ***:This study applied a cross-sectional approach within community settings in a southern province of Vietnam.A structured questionnaire featuring socio-demographic information and common long COVID symptoms was *** correlation coefficients assessed associations among pairs of long COVID ***,multivariable logistic regression models were performed to investigate the risk factors of long COVID in recovered COVID-19 children and ***:Among 422 participants,39.3%reported long COVID symptoms,with a prevalence of 45.2%(SD=0.5)in children and 22.2%(SD=0.4)in *** symptoms reported were cough 34.6%(SD=0.5),fatigue 20.6%(SD=0.4),shortness of breath 10.9%(SD=0.3),and lack of appetite 6.6%(SD=0.3).Concerning risk factors of long COVID,a higher risk was observed among demographic groups,including girls(OR 1.25,95%CI 1.15-1.37;Plescents(OR 1.24,95%CI 1.12-1.37;Ple dose(OR 1.35,95%CI 1.10-1.64;P=0.004)compared to those who have received two ***,patients with a COVID-19 treatment duration exceeding two weeks also had a higher risk of long COVID(OR 1.32,95%CI 1.09-1.60;P=0.003)than those who recovered less than seven ***:The insights from this study provide crucial guidance for predicting the factors associated with the occurrence of long COVID in pediatric patients,contributing to strategic interventions aimed at mitigating the long COVID risks among children and adolescents in Vietnam.

关键词： Long COVID Prevalence Risk factors Children Adolescent Vietnam

Random vibration analysis of FGM plates subjected to moving load using a refined stochastic finite element method

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Defence Technology（防务技术） 2024年第4期34卷 42-56页

作者： Ngoc-Tu Do Trung thanh Tran Faculty of Mechanical Engineering Hanoi University of IndustryHanoiViet Nam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam

The article introduces a finite element procedure using the bilinear quadrilateral element or four-node rectangular element(namely Q4 element) based on a refined first-order shear deformation theory(rFSDT) and Monte Carlo simulation(MCS), so-called refined stochastic finite element method to investigate the random vibration of functionally graded material(FGM) plates subjected to the moving *** advantage of the proposed method is to use r-FSDT to improve the accuracy of classical FSDT, satisfy the stress-free condition at the plate boundaries, and combine with MCS to analyze the vibration of the FGM plate when the parameter inputs are random quantities following a normal distribution. The obtained results show that the distribution characteristics of the vibration response of the FGM plate depend on the standard deviation of the input parameters and the velocity of the moving ***, the numerical results in this study are expected to contribute to improving the understanding of FGM plates subjected to moving loads with uncertain input parameters.

关键词： FGM Moving load R-FSDT Q4 element Monte Carlo simulation Random vibration