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Communications in Theoretical Physics 2019年第8期71卷 947-954页

作者： nguyen Huy Bang le nguyen mai anh nguyen Tien Dung le Van Doai Vinh University 182 Le Duan Street Vinh City Vietnam Nong Lam University Ho Chi Minh City Vietnam (Received March 21 2019revised manuscript

We present a comparative study of the control of group velocity in three-level atomic systems including Λ-, Ladder-, and V-types via spontaneously generated coherence(SGC) and relative phase of laser *** the steady regime, expressions of group index are derived as an analytical function of controllable parameters related to SGC and relative *** is shown that the group velocity can be further slowed down or speeded up under SGC in which modifications of group velocity due to the SGC in Λ-and V-systems are stronger than that in *** particular, when interference strength of SGC p increases from 0.7 to 1.0, the light propagation is switched from superluminal to subluminal modes(for Λ-and Ladder-systems) or from subluminal to superluminal modes(for Vsystem).In the presence of relative phase, the group velocity changes between subluminal and superluminal modes with a period of 2π.In resonant region, the largest positive value of group index reaches at the relative phase φ=π while the largest negative value of group index reaches at φ= 0 and 2π for the Λ-and Ladder-systems, otherwise, for the V-system the largest positive group index occurs at φ= 0 and 2π, and the largest negative group index occurs at φ=π.

关键词： electromagnetically induced transparency spontaneously generated coherence group velocity

Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine learning Models

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 467-500页

作者： Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine learning Models Duc-Dam nguyen nguyen Viet Tiep Quynh-anh Thi Bui Hiep Van le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham Faculty of Civil Engineering University of Transport TechnologyThanh XuanHa Noi100000Vietnam Faculty of Hydraulic Engineering Hanoi University of Civil EngineeringHa Noi100000Vietnam DDG(R)Geological Survey of India Gandhinagar382010India Research Institute of the University of Bucharest Bucharest050663Romania National Institute of Hydrology and Water Management Bucharest013686Romania Department of Civil Engineering Transilvania University of BrasovBrasov500152Romania Danube Delta National Institute for Research and Development Tulcea820112Romania Marwadi University Research Center(MURC) Marwadi UniversityRajkotGujaratBharat360003India Department of Civil Engineering Faculty of Engineering&TechnologyMarwadi UniversityRajkotGujaratBharat360003India

This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and ***,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and *** models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to *** factors were instrumental in predicting the output variable,which was the probability of landslide *** analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other *** AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of *** results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making.

关键词： Landslide susceptibility map spatial analysis ensemble modelling information values(IV)

Regularization of the Inverse Problem for Time Fractional Pseudo-parabolic Equation with Non-local in Time Conditions

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Acta Mathematica Sinica,English Series 2022年第12期38卷 2199-2219页

作者： nguyen Duc PHUONG le Dinh LONG anh Tuan nguyen Dumitru BAleANU Faculty of Fundamental Science Industrial University of Ho Chi Minh CityVietnam Division of Applied Mathematics Science and Technology Advanced InstituteVanLang UniversityHoChi Minh CityVietnam Faculty of Technology Van Lang UniversityHo Chi Minh CityVietnam Department of Mathematics Cankaya UniversityAnkaraTurkey lebanese AmericanUniversity BeirutLebanon Institute of Space Sciences Magurele-BucharestRomania

This paper is devoted to identifying an unknown source for a time-fractional diffusion equation in a general bounded ***,we prove the problem is non-well posed and the stability of the source ***,by using the Modified Fractional Landweber method,we present regularization solutions and show the convergence rate between regularization solutions and sought solution are given under a priori and a posteriori choice rules of the regularization parameter,***,we present an illustrative numerical example to test the results of our theory.

关键词： Source problem fractional pseudo-parabolic problem ill-posed problem convergence estimates regularization

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

An Efficient Adaptive Hierarchical Sliding Mode Control Strategy Using Neural Networks for 3D Overhead Cranes

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International Journal of Automation and computing 2019年第5期16卷 614-627页

作者： Viet-anh le Hai-Xuan le Linh nguyen Minh-Xuan Phan Department of Automatic Control Hanoi University of Science and TechnologyHanoi 10000Vietnam Centre for Autonomous Systems University of Technology SydneyNew South Wales 2007Australia

In this paper, a new adaptive hierarchical sliding mode control scheme for a 3D overhead crane system is proposed. A controller is first designed by the use of a hierarchical structure of two first-order sliding surfaces represented by two actuated and un-actuated subsystems in the bridge crane. Parameters of the controller are then intelligently estimated, where uncertain parameters due to disturbances in the 3D overhead crane dynamic model are proposed to be represented by radial basis function networks whose weights are derived from a Lyapunov function. The proposed approach allows the crane system to be robust under uncertainty conditions in which some uncertain and unknown parameters are highly difficult to determine. Moreover, stability of the sliding surfaces is proved to be guaranteed. Effectiveness of the proposed approach is then demonstrated by implementing the algorithm in both synthetic and reallife systems, where the results obtained by our method are highly promising.

关键词： 3D overhead crane adaptive control hierarchical sliding mode control neural network radial basis function

Discrete-time sliding mode control with power rate exponential reaching law of a pneumatic artificial muscle system

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Control Theory and Technology 2022年第4期20卷 514-524页

作者： Quy-Thinh Dao Trung-Kien le Tri Van-anh nguyen Manh-Linh nguyen School of Electrical and Electronic Engineering Hanoi University of Science and TechnologyDai Co VietHanoi 11615Vietnam

This paper develops a discrete-time sliding mode controller with a power rate exponential reaching law approach to enhance the performance of a pneumatic artificial muscle system in both reaching time and chattering *** proposed method dynamically adapts to the variation of the switching function,which is based on an exponential term and a power rate term of the sliding ***,the controlled system can achieve high tracking performance while still obtain chattering-free ***,the effectiveness of the proposed method is validated through multiple experimental tests,focused on a dual pneumatic artificial muscle ***,experimental results show the effectiveness of the proposed approach in this paper.

关键词： Pneumatic artificial muscle Discrete-time sliding mode control Exponential reaching law Chattering

Effective Evaluation of Using PIDOTIMOD in Treatment of Refractory Allergic Rhinitis

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Effective Evaluation of Using PIDOTIMOD in Treatment of Refr...

作者： mai nguyen Quynh anh 大连医科大学

学位级别：硕士

目的观察匹多莫德对难治性过敏性鼻炎的治疗作用。方法研究以2019年8月至2020年8月期间于大连医科大学附属第一医院耳鼻喉科门诊诊断难治性过敏性鼻炎的68名患者为研究对象。患者随机分为两组,实验组和对照组。所有患者在治疗前均填写... 详细信息

目的观察匹多莫德对难治性过敏性鼻炎的治疗作用。方法研究以2019年8月至2020年8月期间于大连医科大学附属第一医院耳鼻喉科门诊诊断难治性过敏性鼻炎的68名患者为研究对象。患者随机分为两组,实验组和对照组。所有患者在治疗前均填写症状评分问卷,并进行鼻内窥镜检查,对鼻甲肿胀程度和鼻部分泌物情况进行评分。对照组患者给予口服抗组胺药和鼻喷布地奈德治疗;实验组患者在常规治疗基础上额外给予匹多莫德40mg,日两次口服。对比两组治疗前、治疗后两周、治疗后四周鼻部症状评分和鼻内窥镜检查评分评估匹多莫德治疗难治性过敏性鼻炎的临床效果。两组间比较采用配对T检验和Winconxon符号秩检验。结果治疗前对照组鼻部症状评分在鼻塞、流涕、鼻部刺痒感和喷嚏的得分分别是3.31±0.693,3.25±0.672,3.44±0.716,和 3.19±0.53;实验组分别是 3.22±0.659,2.75±0.672,3.16±0.723和2.94±0.669。两组之间差异无统计学意义(P>0.05)。鼻内窥镜下下鼻甲肿胀和鼻分泌物量评分在对照组分别是1.81±0.397,和2.69±0.471,实验组分别是1.84±0.369和2.47±0.621,差异无统计学意义(P>0.05)。治疗后两周对照组鼻部症状评分在鼻塞、流涕、鼻部刺痒感和喷嚏的得分分别是 2.94±0.669,2.81±0.644,2.75±0.762,和 2.44±0.504。实验组鼻部症状评分分别是 1.13±0.751,1.19±0.965,1.03±0.822,和 1.03±0.782。实验组较对照组在上述症状分别多下降1.81±0.082(61.56%),1.62±0.321(57.65%),1.72±0.06(62.54%),和1.41±0.278(57.78%),两组间比较,差异有统计学意义(P<0.05)。对照组鼻内窥镜下下鼻甲肿胀和鼻分泌物量评分分别是1.44±0.504和2.13±0.609;实验组分别是0.53±0.507和0.91±0.777,实验组下鼻甲肿胀和鼻内分泌物评分比对照组分别降低0.91±0.003(63.19%)和1.22±0.168(57.27%),两组对比差异有统计学意义(P<0.05)。治疗4周后对照组鼻塞、流涕、鼻部刺痒感和喷嚏的症状评分是0.47±0.507,0.50±0.508,0.44±0.564,和0.34 ± 0.483。实验组症状改善更多,比对照组减低1.84±0.186(79.65%),1.44±0.161(74.22%),1.69±0.143(79.34%),和 1.41±0.189(80.57%),差异有统计学意义(P<0.05)。对照组鼻内窥镜评分分别是1.19±.644和2.00±0.508,实验组评分分别为0.06±0.246和0.19±0.397,两组对比,实验组下鼻甲肿胀和鼻内分泌物评分比对照组分别降低1.13±0.398(94.95%)和1.81±0.111(90.5%)(P<0.05)。结论匹多莫德可以提高机体免疫力,辅助抗组胺药和鼻喷激素应用可以快速控制难治性过敏性鼻炎的临床症状和体征。

关键词：过敏性鼻炎过敏原免疫治疗匹多莫德

A New Inertial Self-adaptive Gradient Algorithm for the Split Feasibility Problem and an Application to the Sparse Recovery Problem

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Acta Mathematica Sinica,English Series 2023年第12期39卷 2489-2506页

作者： nguyen The VINH Pham Thi HOAI le anh DUNG Yeol Je CHO Department of Mathematical Analysis University of Transport and Communications3 Cau Giay StreetHanoiVietnam Department of Applied Mathematics School of Applied Mathematics and InformaticsHano University of Science and Technology1 Dai Co Viet RoadHanoiVietnam Department of Mathematics and Informatics Hanoi University of Education136 Xuan ThuyCau GiayHanoiVietnam Department of Mathematics Education Gyeongsang National UniversityJinju52828Republicof Korea

In this paper,by combining the inertial technique and the gradient descent method with Polyak's stepsizes,we propose a novel inertial self-adaptive gradient algorithm to solve the split feasi-bility problem in Hilbert spaces and prove some strong and weak convergence theorems of our method under standard *** examine the performance of our method on the sparse recovery prob-lem beside an example in an infinite dimensional Hilbert space with synthetic data and give some numerical results to show the potential applicability of the proposed method and comparisons with related methods emphasize it further.

关键词： Split feasibility problem CQ algorithm Hilbert space sparse recovery problem

An exploration of meteorological effects on PM_(2.5) air quality in several provinces and cities in Vietnam

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Journal of Environmental Sciences 2024年第11期145卷 139-151页

作者： Giang Tran Huong nguyen Luan Thien La Huy Hoang-Cong anh Hoang le Faculty of Chemistry and Environment Dalat UniversityLam Dong ProvinceVietnam Environmental Protection Agency Lam Dong Province Department of Natural Resources and EnvironmentLam Dong ProvinceVietnam Northern Center for Environmental Monitoring Environmental Pollution Control DepartmentHa Noi CityVietnam Faculty of Environment University of ScienceHo Chi Minh CityVietnam Vietnam National University Ho Chi Minh CityVietnam

Linking meteorology and air pollutants is a key *** study investigated meteorological effects on PM_(2.5)concentration using the advanced convergent cross mapping method,utilizing hourly PM_(2.5)concentration and six meteorological factors across eight provinces and cities in *** demonstrated that temperature(ρ=0.30)and radiation(ρ=0.30)produced the highest effects,followed by humidity(ρ=0.28)and wind speed(ρ=0.24),while pressure(ρ=0.22)and wind direction(ρ=0.17)produced the weakest effects on PM_(2.5)*** theρvalues showed that temperature,wind speed,and wind direction had greater impacts on PM_(2.5)concentration during the dry season whereas radiation had a more influence during the wet season;Southern stations experienced larger meteorological ***,humidity,pressure,and wind direction had both positive and negative influences on PM_(2.5)concentration,while radiation and wind speed mostly had negative *** PM_(2.5)pollution episodes,there wasmore contribution ofmeteorological effects on PM_(2.5)concentration indicated byρ*** contaminated levels,humidity(ρ=0.45)was the most dominant factor affecting PM_(2.5)concentration,followed by temperature(ρ=0.41)and radiation(ρ=0.40).Pollution episodes were pointed out to be more prevalent under higher humidity,higher pressure,lower temperature,lower radiation,and lower wind ***ρcalculation also revealed that lower temperature,lower radiation,and higher humidity greatly accelerated each other under pollution episodes,further enhancing PM_(2.5)*** findings contributed to the literature on meteorology and air pollution interaction.

关键词： Fine particulate matter Air pollution Meteorological effect Convergent cross mapping Causality analysis Vietnam

Building 3D CityGML models of mining industrial structures using integrated UAV and TLS point clouds

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International Journal of Coal Science & Technology 2023年第5期10卷 158-177页

作者： Canh le Van Cuong Xuan Cao anh Ngoc nguyen Chung Van Pham Long Quoc nguyen Department of Mine Surveying Hanoi University of Mining and GeologyHanoiVietnam Viettel Group Viettel Cyberspace CenterHanoiVietnam

Mining industrial areas with anthropogenic engineering structures are one of the most distinctive features of the real world.3D models of the real world have been increasingly popular with numerous applications,such as digital twins and smart factory *** this study,3D models of mining engineering structures were built based on the CityGML *** collecting spatial data,the two most popular geospatial technologies,namely UAV-SfM and TLS were *** accuracy of the UAV survey was at the centimeter level,and it satisfied the absolute positional accuracy requirement of creat-ing all levels of detail(LoD)according to the CityGML ***,the UAV-SfM point cloud dataset was used to build LoD 2 *** addition,the comparison between the UAV-SfM and TLS sub-clouds of facades and roofs indicates that the UAV-SfM and TLS point clouds of these objects are highly consistent,therefore,point clouds with a higher level of detail and accuracy provided by the integration of UAV-SfM and TLS were used to build LoD 3 *** resulting 3D CityGML models include 39 buildings at LoD 2,and two mine shafts with hoistrooms,headframes,and sheave wheels at LoD3.

关键词： 3D modelling CityGML-Mining industry UAV Terrestrial laser scanning Point cloud