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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)

Dynamic Modeling of a Non-Uniform Flexible Tail for a Robotic Fish

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Journal of Bionic Engineering 2013年第2期10卷 201-209页

作者： phi Luan nguyen Van Phu Do Byung Ryong Lee Intelligent Control and Mechatronics Lab School of Mechanical Engineering University of Ulsan Ulsan 680-749 Korea School of Mechanical Engineering University of Ulsan Ulsan 680-749 Korea

In this paper, a non-uniform flexible tail of a fish robot was presented and the dynamic model was developed. In this model, the non-uniform flexible tail was modeled by a rotary slender beam. The hydrodynamics forces, including the reactive force and resistive force, were analyzed in order to derive the governing equation. This equation is a fourth-order in space and second-order in time Partial Differential Equation （PDE） of the lateral movement function. The coefficients of this PDE were not constants because of the non-uniform beams, so they were approximated by exponential functions in order to obtain an analytical solution. This solution describes the lateral movement of the flexible tail as a function of material, geometrical and actuator properties. Experiments were then carried out and compared to simulations. It was proved that the proposed model is suitable for predicting the real behavior of fish robots.

关键词： fish robot flexible tail dynamic modeling kinematic lateral movement

Dynamic Modeling and Experiment of a Fish Robot with a Flexible Tail Fin

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Journal of Bionic Engineering 2013年第1期10卷 39-45页

作者： phi Luan nguyen Van Phu Do Byung Ryong Lee ~ Intelligent Control and Mechatronics Lab School of Mechanical Engineering University of Ulsan Daehak-ro 93 Nam-gu Ulsan 680-749 South Korea School of Mechanical Engineering University of Ulsan Daehak-ro 93 Nam-gu Ulsan 680-749 South Korea

This paper presents the dynamic modeling of a flexible tail for a robotic fish. For this purpose firstly, the flexible tail was simplified as a slewing beam actuated by a driving moment. The governing equation of the flexible tail was derived by using the Euler-Bernoulli theory. In this equation, the resistive forces were estimated as a term analogous to viscous damping. Then, the modal analysis method was applied in order to derive an analytical solution of the governing equation, by which the relationship between the driving moment and the lateral movement of the flexible tail was described. Finally, simulations and experiments were carried out and the results were compared to verify the accuracy of the dynamic model. It was proved that the dynamic model of a fish robot with a flexible tail fin well explains the real behavior of robotic fish in underwater environment.

关键词： robotic fish flexible tail dynamic modeling lateral movement

Thrust and Swimming Speed Analysis of Fish Robot with Non-uniform Flexible Tail

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Journal of Bionic Engineering 2016年第1期13卷 73-83页

作者： phi Luan nguyen Byung Ryong Lee Kyoung Kwan Ahn School of Mechanical Engineering University of Ulsan Ulsan Korea

We present a dynamic model of a fish robot with a Non-uniform Flexible Tail （NFT）. We investigate the tendencies of the thrust and swimming speed when the input driving moment changes. Based on the proposed dynamic model of the NFT, we derive the thrust estimation, equation of motion, and performance evaluation of a fish robot with a NFT. By defining the optimal stiffness of the NFT in simulation, a fish robot prototype is then designed and fabricated. A series of experiments are performed to verify the proposed model. Experiment results are in good agreement with simulation data. The results show that the thrust and swimming speed of the fish robot are proportional to the amplitude of the driving moment. There are two resonant fre- quencies （f = 1.4 Hz and 2.2 Hz）, the maximum thrust and swimming speed （about 0.7 BL.s-1） are found to be around f = 1.4 Hz. The above results inidicate the proposed model is suitable for predicting the behavior, thrust and swimming speed of a fish robot with a NFT.

关键词： fish robot flexible tail dynamic modeling swimming speed thrust Froude efficiency

A study on flow fields and performance of water wheel turbine using experimental and numerical analyses

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Science China(Technological Sciences) 2018年第3期61卷 464-474页

作者： nguyen Manh hung JEONG Haechang YANG Changjo Graduate School Division of Marine Engineering Mokpo National Maritime University Department of Marine Engineering Mokpo National Maritime University

In this paper, an analysis of the performance and flow fields of water wheel turbines for tidal energy extraction is carried out using experimental and numerical methods. The purpose of this work is to develop a water turbine suitable for sites, where fast and shallow surface flows are available, such as rivers or tidal currents. For both methods, the water wheel turbine is tested over a range of tip speed ratios with a differing number of rotor blades, ranging between three and twelve. The results indicate that the numerical simulation shows agreement with the experiment in most cases. Also, the water wheel turbine operates effectively at a range of small tip-speed ratios, where the highest turbine efficiency is produced. Under the same working conditions, the turbines using between six and nine blades generate a greater efficiency and cause lesser reverse flows than others when submerged in water. In contrast, the 3-bladed turbine is the least efficient design as it produces the lowest amount of energy and causes intense vibrations and noises. These noises are a result of a collision between the incoming flow of the channel and the wheel blades during the experimentation, especially at high load conditions. By adding more blades, the torque generated is improved considerably; however, the upstream and downstream depths of the turbine, in this case, are also elevated ***, in the inlet region, the 3-bladed and 6-bladed turbines have a smaller shock loss and a lower resistance to the main flow from the inlet than the others. Meanwhile, it is found that the flow in the outlet region on the turbines with between nine and twelve blades is in the opposite direction to the wheel's rotation, significantly obstructing the main flow from the inlet.

关键词： water wheel tidal energy tip speed ratio the number of blades

维普期刊数据库

Spatial prediction of rainfall-induced shallow landslides using hybrid integration approach of Least-Squares Support Vector Machines and differential evolution optimization:a case study in Central Vietnam

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International Journal of Digital Earth 2016年第11期9卷 1077-1097页

作者： Dieu Tien Bui Binh Thai Pham Quoc phi nguyen Nhat-Duc Hoang Geographic Information System Group Department of Business Administration and Computer ScienceUniversity College of Southeast NorwayBøi TelemarkNorway Faculty of Geomatics and Land Administration Hanoi University of Mining and GeologyHanoiVietnam Department of Civil Engineering Gujarat Technological UniversityAhmedabadGujaratIndia Department of Geotechnical Engineering University of Transport TechnologyHa NoiVietNam Department of Environmental Sciences Hanoi University of Mining and GeologyHanoiVietnam Faculty of Civil Engineering Institute of Research and DevelopmentDuy Tan UniversityDanangVietnam

This study represents a hybrid intelligence approach based on the differential evolution optimization and Least-Squares Support Vector Machines for shallow landslide prediction,named as *** LSSVM is used to establish a landslide prediction model whereas the DE is adopted to search the optimal tuning parameters of the LSSVM *** this research,a GIS database with 129 historical landslide records in the Quy Hop area(Central Vietnam)has been collected to establish the hybrid *** receiver operating characteristic(ROC)curve and area under the curve(AUC)were used to assess the performance of the newly constructed *** results show that the proposed model has high performances with approximately 82%of AUCs on both training and validating *** model’s results were compared with those obtained from other methods,Support Vector Machines,Multilayer Perceptron Neural Networks,and J48 Decision *** result comparison demonstrates that the DE-LSSVMSLP deems best suited for the dataset at hand;therefore,the proposed model can be a promising tool for spatial prediction of rainfall-induced shallow landslides for the study area.

关键词： Shallow landslide Least-Squares Support Vector Machines differential evolution GIS Vietnam

Privacy-preserving explainable AI: a survey

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Science China(Information Sciences) 2024年

作者： Thanh Tam nguyen Thanh Trung HUYNH Zhao REN Thanh Toan nguyen phi Le nguyen Hongzhi YIN Quoc Viet hung nguyen School of Information and Communication Technology Griffith University School of Computer and Communication Sciences Ecole Polytechnique Federale de Lausanne Faculty of Mathematics and Computer Science University of Bremen Faculty of Information Technology HUTECH University Department of Computer Science Hanoi University of Science and Technology School of Electrical Engineering and Computer Science The University of Queensland

As the adoption of explainable AI (XAI) continues to expand, the urgency to address its privacy implications intensifies. Despite a growing corpus of research in AI privacy and explainability, there is little attention on privacy-preserving model explanations. This article presents the first thorough survey about privacy attacks on model explanations and their countermeasures. Our contribution to this field comprises a thorough analysis of research papers with a connected taxonomy that facilitates the categorization of privacy attacks and countermeasures based on the targeted explanations. This work also includes an initial investigation into the causes of privacy leaks. Finally, we discuss unresolved issues and prospective research directions uncovered in our analysis. This survey aims to be a valuable resource for the research community and offers clear insights for those new to this domain. To support ongoing research, we have established an online resource repository, which will be continuously updated with new and relevant findings.

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Study of relationship between motion of mechanisms in gas operated weapon and its shock absorber

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Defence Technology（防务技术） 2024年第3期33卷 42-54页

作者： Jiri Balla Roman Vitek Dung nguyen Van Zbynek Krist hung nguyen Van Department of Weapons and Ammunition University of Defence BrnoCzech Republic Department of Weapons Le Quy Don Technical UniversityHanoiViet Nam Department of Design and Special Engineering Alexander Dubcek University of TrencinSlovakia

The article deals with the motion of the breech block carrier and the weapon casing of an automatic weapon mounted on a flexible carriage and the base of the *** works,which did not consider the dynamic properties of the base of the weapon,did not allow to reconcile the calculated and experimental results of the weapon casing displacement when shooting from firing *** the analysis of the motion of individual parts,the methods of mathematical modelling and firing experiments using a high-speed camera were *** show the best accord with experiment when modelling the system with 4 degrees of *** oscillation of the system regarding the movement of the breech block carrier and the weapon casing was investigated under changed conditions of rate of fire,the use of a muzzle brake and different types of shock *** velocities and displacements of the weapon casing and the breech block carrier at different values of the impulse of the gases to the breech block carrier were determined.

关键词： Shock absorber Gas-operated weapon Force-impulse diagram Recoil system Breech block carrier

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Insights and implications from the study on meniscus reconstruction using tendon autograft

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World Journal of Orthopedics 2024年第11期15卷 1109-1111页

作者： phi Duong nguyen Thanh Kien Lam Department of Orthopaedic-Burn-Plastic Surgery City Children's HospitalHo Chi Minh City 71815Viet Nam The Faculty of Medical Technology Van Lang UniversityHo Chi Minh City 700000Viet Nam

This letter addresses the recent study by Zhu et al on the predictive factors for coronal and sagittal graft extrusion length following medial meniscus reconstruction using tendon *** study provides valuable insights into the importance of preoperative joint space width and tunnel positioning as predictors of graft ***,it found strong correlations between preoperative joint space width and medial,posterior,and mean graft extrusion at both 1 week and 8 months ***,tunnel edge distance at 1 week postoperation correlated with anterior and posterior graft *** findings offer critical guidance for improving surgical ***,the letter highlights the need for further research with larger sample sizes and comparative studies involving different graft types to strengthen these findings and broaden their applicability in clinical *** study's contributions to understanding meniscus reconstruction using tendon autografts are acknowledged,along with suggestions for future research directions.

关键词： Meniscus reconstruction Tendon autograft Graft extrusion Joint space width Tunnel positioning Surgical outcomes