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基于RUN-XGBoost算法的土石坝渗流预测模型 被引量:1
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作者 马春辉 侯媛媛 +2 位作者 杨杰 袁帅 徐笑颜 《水利水电科技进展》 CSCD 北大核心 2024年第2期72-78,共7页
针对传统土石坝渗流预测模型存在局部最优、抗干扰性差和预测精度低等问题,通过RUN算法优化XGBoost算法得到RUN-XGBoost算法,构建了RUN-XGBoost模型以获得更优的土石坝渗流预测结果。该模型在种群初始化时采用RUN算法对XGBoost算法的3... 针对传统土石坝渗流预测模型存在局部最优、抗干扰性差和预测精度低等问题,通过RUN算法优化XGBoost算法得到RUN-XGBoost算法,构建了RUN-XGBoost模型以获得更优的土石坝渗流预测结果。该模型在种群初始化时采用RUN算法对XGBoost算法的3个主要参数进行改进,使预测结果有较高的有效性;通过自动寻找最优参数增进算法的整体收敛速度和预测精度,同时引入随机解,使算法能够排除局部最小值并继续搜索,从而获得全局最优结果。工程实例验证结果表明,RUN-XGBoost模型具有简洁、高效、预测精度高、鲁棒性强等优点。 展开更多
关键词 土石坝 渗流监测 run-XGBoost算法 预测模型
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半导体生产过程的Run-to-Run控制技术综述 被引量:4
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作者 王树青 张学鹏 陈良 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2008年第8期1393-1398,1457,共7页
Run-to-Run通过对历史批次过程数据的统计分析改变下一批次的制程方案(recipe),解决间歇过程尤其是半导体生产过程中在线测量手段缺乏造成实时过程控制难以实施的问题,从而降低批次间产品的品质差异.这一方法是统计过程控制和实时控制... Run-to-Run通过对历史批次过程数据的统计分析改变下一批次的制程方案(recipe),解决间歇过程尤其是半导体生产过程中在线测量手段缺乏造成实时过程控制难以实施的问题,从而降低批次间产品的品质差异.这一方法是统计过程控制和实时控制的折中,提供了一个提升产品质量、改善总体设备效能的框架.介绍了Run-to-Run控制的产生背景,阐述了Run-to-Run控制器的一般结构,重点介绍了3类主要的Run-to-Run控制算法,对各种Run-to-Run控制算法进行了评价,并介绍了它们在关键单元操作中的应用,最后探讨了未来的研究方向. 展开更多
关键词 run-to-Run控制 间歇过程 半导体生产 统计过程控制
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RUN-124缓蚀剂在加氢装置的应用
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作者 殷磊 王涛 朱力勇 《石化技术》 CAS 2018年第2期39-40,共2页
本文分析了缓蚀剂防腐机理,通过具体的应用实例阐述了RUN-124缓蚀剂在加氢装置的应用,该缓释剂能够在塔顶空冷和工艺管线表面形成缓蚀膜,改善HCl-H_2S-H_2O腐蚀体系对设备的腐蚀,但只适用原料品质优、操作条件缓和的加氢装置,适应范围小。
关键词 run-124缓蚀剂 加氢装置 应用
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A prediction model for horizontal run-out distance of landslides triggered by Wenchuan earthquake 被引量:6
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作者 Yang Changwei Zhang Jianjing Zhang Ming 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第2期201-208,共8页
The peak ground acceleration (PGA), the volume of a sliding mass V, the height of a mountain HL and the slope angle θ of a mountain are four important parameters affecting the horizontal run-out distance of a lands... The peak ground acceleration (PGA), the volume of a sliding mass V, the height of a mountain HL and the slope angle θ of a mountain are four important parameters affecting the horizontal run-out distance of a landslide L. Correlations among them are studied statistically based on field investigations from 67 landslides triggered by the ground shaking and other factors during the Wenchuan earthquake, and then a prediction model for horizontal run-out distance L is developed in this study. This model gives due consideration to the implications of the above four parameters on the horizontal run-out distance L and the validity of the model is verified by the Donghekou and Magong Woqian landslides. At the same time, the advantages of the model are shown by comparing it with two other common prediction methods. The major findings drawn from the analyses and comparisons are: (1) an exponential relationship exists between L and log V, L and log HL, L and log PGA separately, but a negative exponential relationship exists between L and log tan0, which agrees with the statistical results; and (2) according to the analysis results of the relative relationship between the height of a mountain (H) and the place where the landslides occur, the probabilities at distances of2H/3-H, H/3-2H/3, and O-H/3 are 70.8%, 15.4%, and 13.8%, respectively, revealing that most landslides occurred at a distance of H/2-H. This prediction model can provide an effective technical support for the prevention and mitigation of landslide hazards. 展开更多
关键词 Wenchuan earthquake LANDSLIDES run-out distance prediction model relationship
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Effect of Berm Width and Elevation on Irregular Wave Run-Up 被引量:7
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作者 Chen Guoping , Yu Kuang-ming and Zhang Jiachang Assistant Engineer, River and Harbour Department, Nanjing Hydraulic Research Institute, NanjingProf. and Senior Engineer, River and Harbour Department, Nanjing Hydraulic Research Institute, Nanjing Senior Engineer, River and Harbour Department, Nanjing Hydraulic Research Institute, Nanjing 《China Ocean Engineering》 SCIE EI 1991年第4期441-452,共12页
This paper discusses the effect of berm width and elevation of composite slope on irregular wave run-up. Based on the data obtained from model tests, the formula and distribution of irregular wave run-up on composite ... This paper discusses the effect of berm width and elevation of composite slope on irregular wave run-up. Based on the data obtained from model tests, the formula and distribution of irregular wave run-up on composite slope are derived. The changing of wind speed, width and elevation of the berm are considered comprehensively. The wave run-up with various exceedance probability can be es-timated utilizing the distribution curves of irregular wave run-up. 展开更多
关键词 berm width berm elevation irregular wave run-up composite slope
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Numerical Investigation of Run-ups on Cylinder in Steep Regular Wave 被引量:2
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作者 FAN Xiang ZHANG Jing-xin LIU Hua 《China Ocean Engineering》 SCIE EI CSCD 2019年第5期601-607,共7页
The run-up on offshore structures induced by the steep regular wave is a highly nonlinear flow with a free surface. This article focuses on the investigation of the steep regular wave run-up on a single vertical cylin... The run-up on offshore structures induced by the steep regular wave is a highly nonlinear flow with a free surface. This article focuses on the investigation of the steep regular wave run-up on a single vertical cylinder by solving the Navier-Stokes equations. A numerical wave tank is established based on the open-source package to simulate the wave scattering induced by a vertical cylinder. The VOF method is applied to capture the large deformation and breaking of the free surface. The numerical model is validated by experimental results. The relative wave run-ups on the front face and the back face along the centerline of a cylinder are analyzed. The changes of the relative run-ups with the wave steepness, the relative diameter and the relative depth are studied. It is found that the relative run-ups on the front face and the back face of the cylinder depend mainly on the wave steepness and the relative diameter, while the dependence on the relative depth is weak. The empirical formulae are proposed to calculate the relative run-ups in terms of the wave steepness of incident regular waves and the relative diameter of a cylinder. 展开更多
关键词 STEEP REGULAR wave vertical CYLINDER run-UP empirical FORMULA numerical experiments
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New Algorithm for Binary Connected-Component Labeling Based on Run-Length Encoding and Union-Find Sets 被引量:3
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作者 王洪涛 罗长洲 +2 位作者 王渝 郭贺 赵述芳 《Journal of Beijing Institute of Technology》 EI CAS 2010年第1期71-75,共5页
Based on detailed analysis of advantages and disadvantages of the existing connected-component labeling (CCL) algorithm,a new algorithm for binary connected components labeling based on run-length encoding (RLE) a... Based on detailed analysis of advantages and disadvantages of the existing connected-component labeling (CCL) algorithm,a new algorithm for binary connected components labeling based on run-length encoding (RLE) and union-find sets has been put forward.The new algorithm uses RLE as the basic processing unit,converts the label merging of connected RLE into sets grouping in accordance with equivalence relation,and uses the union-find sets which is the realization method of sets grouping to solve the label merging of connected RLE.And the label merging procedure has been optimized:the union operation has been modified by adding the "weighted rule" to avoid getting a degenerated-tree,and the "path compression" has been adopted when implementing the find operation,then the time complexity of label merging is O(nα(n)).The experiments show that the new algorithm can label the connected components of any shapes very quickly and exactly,save more memory,and facilitate the subsequent image analysis. 展开更多
关键词 binary images connected-component labeling run-length encoding union-find sets
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Experimental Study on 2-D Focusing Wave Run-up on A Vertical Cylinder 被引量:2
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作者 柳淑学 孙一艳 +1 位作者 李金宣 臧军 《China Ocean Engineering》 SCIE EI 2010年第3期499-512,共14页
In this paper,the focused wave groups with different parameters and their actions on a vertical cylinder are experimentally studied. The harmonic wave characteristics of the focusing waves are analyzed by the addition... In this paper,the focused wave groups with different parameters and their actions on a vertical cylinder are experimentally studied. The harmonic wave characteristics of the focusing waves are analyzed by the addition and subtraction of the crest and trough focusing waves. The analyzed results show that higher order harmonics can be generated because of the interaction of component waves. Nonlinearity increases with the inputted wave amplitude and the frequency width increment. Further, the wave run-up around the vertical circular cylinder is experimentally studied. It increases with the wave steepness and the relative cylinder diameter increase. However, the variations of wave run-up around the circular cylinder are different. The researches provide a reference for further numerical studies. 展开更多
关键词 wave focusing NONLINEARITY vertical circular cylinder wave run-up
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Impedance Analytical Method of Wave Run-up and Reflection from A Slotted-Wall Caisson Breakwater 被引量:3
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作者 朱大同 《China Ocean Engineering》 SCIE EI 2010年第3期453-465,共13页
An impedance analytical method (IAM) is developed to study the interaction of plane water wave with a slotted-wall caisson breakwater. The non-linear boundary condition at the slotted-wall is expressed in terms of f... An impedance analytical method (IAM) is developed to study the interaction of plane water wave with a slotted-wall caisson breakwater. The non-linear boundary condition at the slotted-wall is expressed in terms of flow resistance. A set of algebraic expressions are obtained for free surface elevation inside and outside chamber, and reflection coefficient. The prediction of the reflection coefficients shows that the relative widths of the chamber inducing the minimum reflection coefficient for a slotted-wall caisson breakwater are in a range of 0.10~0.20, which are smaller than that (0.15~0.25) for a perforated-wall caisson breakwater. The reflection coefficients and free surface elevation obtained by the present model are compared with that of laboratory experiments carried out by previous researchers. 展开更多
关键词 plane wave slotted-wall caisson wave reflection wave run-up impedance analytical method (IAM)
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Wave Run-up on A Coaxial Perforated Circular Cylinder 被引量:2
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作者 朱大同 《China Ocean Engineering》 SCIE EI 2011年第2期201-214,共14页
This paper describes a plane regular wave interaction with a combined cylinder which consists of a solid inner column and a coaxial perforated outer cylinder. The outer perforated surface is a thin porous cylinder wit... This paper describes a plane regular wave interaction with a combined cylinder which consists of a solid inner column and a coaxial perforated outer cylinder. The outer perforated surface is a thin porous cylinder with an annular gap between it and the inner cylinder. The non-linear boundary condition at the perforated wall is a prime focus in the study; energy dissipation at the perforated wall occurs through the resistance to the fluid across the perforated wall. Explicit analytical formulae are presented to calculate the wave run-up on the outer and inner surfaces of the perforated cylinder and the surface of the inner column. The theoretical results of the wave run-up are compared with previous experimental data. Numerical results have also been obtained: when the ratio of the annular gap between the two cylinders to incident wavelength (b-a)/L≤0. 1, the wave run-up on the inner surface of the perforated cylinder and the surface of inner column can partially or completely exceed the incident wave height. 展开更多
关键词 plane water wave coaxial perforated cylinder wave run-up flow resistance
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Wave Run-up on A Vertical Seawall Protected by An Offshore Submerged Barrier 被引量:1
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作者 张景新 刘桦 《China Ocean Engineering》 SCIE EI 2009年第3期553-564,共12页
Submerged barriers are constructed in coastal zones for shoreline or harbor protection or to prevent the beach erosion. In the present study, the wave run-up on a vertical seawall protected by a submerged barrier is a... Submerged barriers are constructed in coastal zones for shoreline or harbor protection or to prevent the beach erosion. In the present study, the wave run-up on a vertical seawall protected by a submerged barrier is analyzed. The physical configurations include a rigid barrier and a long channel of finite depth. For linear water waves, by matching the velocity along the barrier and along the gap, the systems of linear equations about the velocity potentials are obtained. The wave rim-up is further analyzed for various settings of barrier height and distance between the barrier and the wall, i.e. the chamber length. For nonlinear waves and random sea waves, a numerical model is extended to investigate the effect parameters of the barrier on the wave rim-up against the seawall. Not only the numerical simulations, but also the analytical results illustrate that the wave run-up on the seawall depends very much on the distance between the barrier and the vertical seawall. 展开更多
关键词 submerged barrier standing wave wave run-up
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Critical Factors for Run-up and Impact of the Tohoku Earthquake Tsunami 被引量:1
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作者 Efthymios Lekkas Emmanouil Andreadakis +1 位作者 Irene Kostaki Eleni Kapourani 《International Journal of Geosciences》 2011年第3期310-317,共8页
The earthquake of March 11 of magnitude 9 offshore Tohoku, Japan, was followed by a tsunami wave with particularly destructive impact, over a coastal area extending approx. 850km along the Pacific Coast of Honshu Isla... The earthquake of March 11 of magnitude 9 offshore Tohoku, Japan, was followed by a tsunami wave with particularly destructive impact, over a coastal area extending approx. 850km along the Pacific Coast of Honshu Island. First arrival times and measurements and maximum height were recorded by the Japanese monitoring system (wherever there was no failure of the equipment). The maximum run-up is well evident in satellite images available through USGS, Google and other institutes. Moreover, personal observations of Prof. Lekkas were made during a field survey in March 2011. The results of the study of the tsunami impact and run-up show the variety of factors affecting the run-up, creating zones with similar phenomena, but also specific locations where run-up exceeds by far the run-up zone maximum values. This differentiation, observed also in the past by other authors, is here attributed to the general orientation of the coast, the distance from the tsunami generation area, bathymetry offshore, the coastline morphology and land geomorphology. In certain cases that funnelling and reflection effects in narrow gulfs parallel to the tsunami propagation vector were combined with narrow valleys onshore, peak run-up exceeded 20m, or even 40 m (Miyagi coastline, Ogatsu, Onagawa, etc). 展开更多
关键词 Tohoku EARTHQUAKE TSUNAMI run-UP
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Application of artificial neural network to calculation of solitary wave run-up 被引量:1
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作者 You-xing WEI Deng-ting WANG Qing-jun LIU 《Water Science and Engineering》 EI CAS 2010年第3期304-312,共9页
The prediction of solitary wave run-up has important practical significance in coastal and ocean engineering, but the calculation precision is limited in the existing models. For improving the calculation precision, a... The prediction of solitary wave run-up has important practical significance in coastal and ocean engineering, but the calculation precision is limited in the existing models. For improving the calculation precision, a solitary wave run-up calculation model was established based on artificial neural networks in this study. A back-propagation (BP) network with one hidden layer was adopted and modified with the additional momentum method and the auto-adjusting learning factor. The model was applied to calculation of solitary wave run-up. The correlation coefficients between the neural network model results and the experimental values was 0.996 5. By comparison with the correlation coefficient of 0.963 5, between the Synolakis formula calculation results and the experimental values, it is concluded that the neural network model is an effective method for calculation and analysis of solitary wave ran-up. 展开更多
关键词 solitary wave run-up artificial neural network back-propagation (BP) network additional momentum method auto-adjusting learning factor
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Study on the Simulation and Run-up of Ship Waves of Express Liners in the Zhujiang Delta
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作者 黄海龙 方成 陈国平 《China Ocean Engineering》 SCIE EI 2010年第4期759-770,共12页
Ship waves are observed with wave-generating techniques by way of simulating express liners in the Zhujiang Delta.The analog test study of ship waves is conducted in a wave flume and a wave basin respectively. Thus, d... Ship waves are observed with wave-generating techniques by way of simulating express liners in the Zhujiang Delta.The analog test study of ship waves is conducted in a wave flume and a wave basin respectively. Thus, different wave elements and different incident angles of ship waves are decided; so are different slopes of protection, the plafform, width of plafform, and the influence over the ship wave run-up on protection from armor coat structure. The empirical relation- 展开更多
关键词 ship wave SIMULATION run- up
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Run-Up Flow of a Maxwell Fluid through a Parallel Plate Channel 被引量:1
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作者 Syed Yedulla Qadri M. Veera Krishna 《American Journal of Computational Mathematics》 2013年第4期297-303,共7页
We consider the flow of an incompressible viscous Maxwell fluid between two parallel plates, initially induced by a constant pressure gradient. The pressure gradient is withdrawn and the upper plate moves with a unifo... We consider the flow of an incompressible viscous Maxwell fluid between two parallel plates, initially induced by a constant pressure gradient. The pressure gradient is withdrawn and the upper plate moves with a uniform velocity while the lower plate continues to be at rest. The arising flow is referred to as run-up flow. The unsteady governing equations are solved as initial value problem using Laplace transform technique. The expression for velocity, shear stresses on both plates and discharge are obtained. The behavior of the velocity, shear stresses and mass flux has been discussed in detail with respect to variations in different governing flow parameters and is presented through graphs. 展开更多
关键词 run-UP FLOW Maxwell’s Fluid LAPLACE Transforms REYNOLDS Number and Parallel PLATE CHANNELS
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Constrained Run-to-Run Optimization for Batch Process Based on Support Vector Regression Model
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作者 李赣平 阎威武 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第4期478-483,共6页
An iterative (run-to-run) optimization method was presented for batch processes under input constraints. Generally it is very difficult to acquire an accurate mechanistic model for a batch process.Because support vect... An iterative (run-to-run) optimization method was presented for batch processes under input constraints. Generally it is very difficult to acquire an accurate mechanistic model for a batch process.Because support vector machine is powerful for the problems characterized by small samples,nonlinearity, high dimension and local minima, support vector regression models were developed for the end-point optimization of batch processes. Since there is no analytical way to find the optimal trajectory, an iterative method was used to exploit the repetitive nature of batch processes to determine the optimal operating policy. The optimization algorithm is proved convergent. The numerical simulation shows that the method can improve the process performance through iterations. 展开更多
关键词 run-to-run OPTIMIZATION BATCH process SUPPORT VECTOR regression
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Prediction on Irregular Wave Run-up and Overtopping
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作者 陈国平 严士常 周益人 《China Ocean Engineering》 SCIE EI 2010年第3期481-498,共18页
A series of hydraulic model tests are carried out to investigate random wave run-up and overtopping on smooth, impermeable single slope and composite slope. Based on the analysis of the influences of wave steepness, s... A series of hydraulic model tests are carried out to investigate random wave run-up and overtopping on smooth, impermeable single slope and composite slope. Based on the analysis of the influences of wave steepness, structure slope, incident wave angle, width of the berm and water depth on the berm and the wave run-up, empirical formulas for wave run-up on dike are proposed. Moreover, empirical formula on estimating the wave run-up on composite slope with multiple berms is presented for practical application of complex dike cross-section. The present study shows that the influence factors for wave overtopping are almost the same as those for wave run-up and the trend of the wave overtopping variation with main influence parameters is also similar to that for wave run-up. The trend of the wave overtopping variations can be well described by two main factors, i.e. the wave run-up and the crest freeboard of the structure. A new prediction method for wave overtopping is proposed for random waves. The proposed prediction formulas are applied to case study of over forty cases and the results show that the prediction methods are good enough for practical design purposes. 展开更多
关键词 wave run-up OVERTOPPING oblique wave composite slope
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Experiments on Transformation and Run-Up of Wave Trains
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作者 董国海 李玉成 《China Ocean Engineering》 SCIE EI 2000年第3期329-337,共9页
This paper. details experiments undertaken in the UK Coastal Research Facility (CRF)at Hy draulies Research (HR), Wallingford, on transformation and run-up of wave trains. The purpose of these experiments is to provid... This paper. details experiments undertaken in the UK Coastal Research Facility (CRF)at Hy draulies Research (HR), Wallingford, on transformation and run-up of wave trains. The purpose of these experiments is to provide verification data for numerical models of wave transformation in shoaling. surf and swash zones. This is the kind of data ih:lt flume experiments are unable to provide, and is collected in the highly controlled environment of CRF where extrinsic factors present in the field are not an issue. The experiments concerning wave trains are undertaken by use of existing wave generation software, and the run-up measurements are made with large experimental run-up gauges. 展开更多
关键词 EXPERIMENT TRANSFORMATION wave train run-UP random waves regular waves
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Estimation of Tsunami Run-up Height by Three Artificial Neural Network Methods
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作者 Nuray GEDIK Emel IRTEM +1 位作者 H.Kerem CIGIZOGLU M.Sedat KABDASLI 《China Ocean Engineering》 SCIE EI 2009年第1期85-94,共10页
Tsunami ran-up height is a significant parameter for dimensions of coastal structures. In the present study, tsunami run-up heights are estimated by three different Artificial Neural Network (ANN) models, i.e. Feed ... Tsunami ran-up height is a significant parameter for dimensions of coastal structures. In the present study, tsunami run-up heights are estimated by three different Artificial Neural Network (ANN) models, i.e. Feed Forward Back Propagation (FFBP), Radial Basis Functions (RBF) and Generalized Regression Neural Network (GRNN). As the input for the ANN configuration, the wave height (H) values are employed. It is shown that the tsunami ran-up height values are closely approximated with all of the applied ANN methods. The ANN estimations are slightly superior to those of the empirical equation. It can be seen that the ANN applications are especially significant in the absence of adequate number of laboratory experiments. The results also prove that the available experiment data set can be extended with ANN simulations. This may be helpful to decrease the burden of the experimental studies and to supply results for comparisons. 展开更多
关键词 tsanami run-up height artificial neural network methods EXPERIMENTS
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Effect of Wave Groups on Wave Run-up
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作者 Zhou Jiabao and Zhang Jiachang Senior Engineer, River and Harbour Department, Nanjing Hydraulic Research Institute, Nanjing 《China Ocean Engineering》 SCIE EI 1992年第1期79-86,共8页
-The effect of wave group on wave run-up on a slope dike is mainly discussed in this paper. Two simulating methods of wave group and their applications in laboratory are introduced. Synthesizing the research results o... -The effect of wave group on wave run-up on a slope dike is mainly discussed in this paper. Two simulating methods of wave group and their applications in laboratory are introduced. Synthesizing the research results of wave run-up on a slope dike, the effect of wave group on wave run-up on a slope dike in coastal protection engineering is studied as the main point. 展开更多
关键词 wave group run-UP slope dike coastal protection engineering
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