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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 dept.,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)

Numerical analysis of soil-rock mixture's meso-mechanics based on biaxial test

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Journal of Central South University 2016年第3期23卷 685-700页

作者：张海洋徐文杰于玉贞 State Key Laboratory of Hydroscience and hydraulic engineering Department of Hydraulic Engineering Tsinghua University

Soil-rock mixture(S-RM)is a widely distributed geotechnical medium composed of "soil" and "rock block" different both in size and strength. Internal rock blocks form special and variable meso-structural characteristics of S-RM. The objective of this work was to study the control mechanism of meso-structural characteristics on mechanical properties of S-RM. For S-RM containing randomly generated polygonal rock blocks, a series of biaxial tests based on DEM were conducted. On the basis of research on the effects of rock blocks' breakability and sample lateral boundary type(rigid, flexible) on macroscopic mechanical behavior of S-RM, an expanded Mohr-Coulomb criterion in power function form was proposed to represent the strength envelop. At the mesoscopic level, the variations of meso-structure such as rotation of rock block, and the formation mechanism and evolution process of the shear band during tests were investigated. The results show that for S-RM with a high content of rock block, translation, rotating and breakage of rock blocks have crucial effects on mechanical behavior of S-RM. The formation and location of the shear band inside S-RM sample are also controlled by breakability and arrangement of rock blocks.

关键词： soil-rock mixture (S-RM) meso-structural mechanics (MSM) discrete element method (DEM) rock block breakability lateral boundary type shear band

Generation of 3D random meso-structure of soil-rock mixture and its meso-structural mechanics based on numerical tests

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Journal of Central South University 2015年第2期22卷 619-630页

作者：徐文杰张海洋介玉新于玉贞 State Key Laboratory of Hydroscience and hydraulic engineering(Department of hydraulic engineering Tsinghua University)

The mesoscopic failure mechanism and the macro-mechanical characteristics of soil-rock mixture(S-RM) under external load are largely controlled by S-RM's meso-structural features. The objective of this work is to improve the three-dimensional technology for the generation of the random meso-structural models of S-RM, for randomly generating irregular rock blocks in S-RM with different shapes, sizes, and distributions according to the characteristics of the rock blocks' size distribution. Based on the new improved technology, a software system named as R-SRM3 D for generation and visualization of S-RM is developed. Using R-SRM3 D, a three-dimensional meso-structural model of S-RM is generated and used to study the meso-mechanical behavior through a series of true-triaxial numerical tests. From the numerical tests, the following conclusions are obtained. The meso-stress field of S-RM is influenced by the distribution of the internal rock blocks, and the macro-mechanical characteristics of S-RM are anisotropic in 3D; the intermediate principal stress and the soil-rock interface properties have significant influence on the macro strength of S-RM.

关键词： soil-rock mixture(S-RM) three dimensional meso-structure meso-structural mechanics(M-SM) true-triaxial numerical test random simulation

Fluvial Processes in the Meandering Reach of the Lower Wei River During the Course of Degradation

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四川大学学报（工程科学版） 2005年第S1期37卷 46-51页

作者： Xia, Junqiang Wang, Guangqian Wu, Baosheng dept. of hydraulic Eng. Tsinghua Univ. Beijing 100084 China

This paper presents an analysis of the changes of the longitudinal and lateral profiles in the meander- ing reach of the Lower Wei River over the period from October 1973 to October 1976 during the course of *** results indicated that retrogressive erosion and subsequent downstream erosion occurred in the reach due to the lowering in the Tongguan elevation and the inflowing water carrying low sediment con- *** the end of the degradation,the main channel widths of the majority ...

关键词： the Lower Wei River fluvial processes batse level of erosion channel widening channel undercut

Seismic behavior of concrete filled steel tubular arch structures

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Earthquake engineering and engineering Vibration 2005年第1期4卷 107-115页

作者：熊峰 Sashi K Kunnath 刘浩吾 dept. of Civil engineering Sichuan University Chengdu 610065 ChinaProfessor dept. of Civil and Environmental engineering California University at Davis CA95616 USAProfessor dept. of hydraulic engineering Sichuan University Chengdu 610065 ChinaProfessor

Shaking table tests of a 1:10 scale arch model performed to investigate the seismic behavior and resistance of concrete filled steel tubular (CFT) arch structures are described in this paper. The El-Centro record and Shanghai artificial wave were adopted as the input excitation. The entire test process can be divided into three stages depending on the lateral brace configurations, i.e., fully (five) braced, two braces removed, and all braces removed. A total of 46 tests, starting from the elastic state to failure condition, have been conducted. The natural vibration frequencies, responses of acceleration, displacement and strain were measured. From the test results, it is demonstrated that the CFT arch structures are capable of resisting severe ground motions and that CFT arches offer a credible alternative to reinforced concrete arches, especially in regions of high seismic intensity.

关键词： concrete filled steel tube arch structures shaking table test seismic behavior lateral braces

Flow patterns and boundary conditions for inlet and outlet conduits of large pump system with low head

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Applied Mathematics and Mechanics(English Edition) 2014年第6期35卷 675-688页

作者：徐磊陆伟刚陆林广董雷王兆飞 College of hydraulic Science and engineering Yangzhou University

The flow patterns in the inlet and outlet conduits have a decisive effect on the safe, stable, and highly efficient operation of the pump in a large pumping station with low head. The numerical simulation of three-dimensional （3D） turbulence flow in conduits is an important method to study the hydraulic performance and conduct an optimum hydraulic design for the conduits. With the analyses of the flow patterns in the inlet and outlet conduits, the boundary conditions of the numerical simulation for them can be determined. The main obtained conclusions are as follows：（i） Under normal operation conditions, there is essentially no pre-swirl flow at the impeller chamber inlet of an axial-flow pump system, based on which the boundary condition at the inlet conduit may be defined. （ii） The circulation at the guide vane outlet of an axial-flow pump system has a great effect on the hydraulic performance of the outlet conduit, and there is optimum circulation for the performance. Therefore, it is strongly suggested to design the guide vane according to the optimum circulation. （iii） The residual circulation at the guide vane outlet needs to be considered for the inlet boundary condition of the outlet conduit, and the value of the circulation may be measured in a specially designed test model.

关键词： flow pattern boundary condition inlet conduit outlet conduit pump system low head

Optimal dosing time of acid algaecide for restraining algal growth

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Water Science and engineering 2013年第4期6卷 402-408页

作者： Cui-chao PANG Xin-jian FAN Jie ZHOU Shi-qiang WU hydraulic engineering Department Nanjing Hydraulic Research Institute

Restraining algal growth by algaecide has been studied by many researchers, but the dosing time has not yet been studied. In this study, we examined the appropriate dosing time of algaecide through a series of experiments. In the experiments, the pH value of water is significantly affected by Microcystis aeruginosa, and the variation of the pH value is in favor of the growth of the alga. Therefore, using acid algaecide in the period with maximum pH values, i.e., the stable phase, would change the acidity-alkalinity of the water significantly, and would negatively affect algal growth. Acid algaecide does not eliminate the alga effectively if the acid algaecide is dosed in the logarithmic growth phase. Using acid algaecide in the decline phase after algal bloom not only is unfavorable for eliminating the alga, but also prolongs the decline phase, and even brings about next larger algal bloom.

关键词： Microcystis aeruginosa," algal bloom," acid algaecide dosing time

A COMPUTATIONAL METHOD FOR FIRST-EXCURSION RELIABILITY

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Acta Mechanica Sinica 1996年第4期12卷 377-386页

作者：刘宁 dept.of hydraulic engineering Tsinghua UniversityBeijing 100084China

An efficient computational method is suggested for the first-excursion reliability assessment of nonstationary process. In the proposed method, the nonlinear performance function is Linearized at the Hasofer-Lind point obtained by an iterative algorithm. The problem of the nonstationary processes is solved by the discrete-time method, in which the precision can be controlled by choosing the steps of discretization. The derived formulae can be conveniently degraded to calculate both the first-excursion reliability with linear performance function of stationary processes and the time-independent reliability. The suggested method is useful for the analysis of components and systems with nonstationary responses in structural design where some uncertainties are represented by a vector of nonstationary processes. Examples are given to demonstrate the fast convergency and effectiveness of the presented method.

关键词： structural reliability nonstationary processes nonlinear performance function first-excursion reliability

Three-dimensional saltating processes of multiple sediment particles

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International Journal of Sediment Research 2009年第1期24卷 16-32页

作者： Hsiao-Wen WANG Hong-Yuan LEE Po-Ning LEE dept. of hydraulic and Ocean engineering National Cheng Kung University dept. of Civil engineering National Taiwan University

The purpose of this study was to investigate the interacting mechanism between the saltating particles near a channel bed. A three-dimensional real-time flow visualization technique was developed to measure the interparticle collision behaviors during the saltating process. Based on the experimental data,the distribution of the collision points was found to be symmetric. This confirms the assumption that the projections of the collision points onto the reasonable plane are uniformly distributed. A three-dimensional saltating model was also developed. This model produced satisfactory results. The model is able to simulate the continuous saltating trajectories of several particles. The simulated dimensionless saltating height,longitudinal and vertical saltation velocity components were found to increase as the dimensionless particle diameter and the dimensionless flow transport capacity parameter increase,while the simulated lateral saltation velocity component varies inversely with the dimensionless flow transport capacity parameter. A regression equation for the bed load transport rate was also obtained.

关键词： Interparticle collision Saltation Sediment Three dimension Charged couple device (CCD)