Development of an Interdisciplinary Prediction System Combining Sediment Transport Simulation and Ensemble Method

The change in movable beds is related to the mechanisms of sediment transport and hydrodynamics. Numerical modelling with empirical equations and the simplified momentum equation is the common means to analyze the complicated sediment transport processing in river channels. The optimization of parameters is essential to obtain the proper results. Inadequate parameters would cause errors during the simulation process and accumulate the errors with long-time simulation. The optimized parameter combination for numerical modelling, however, is rarely discussed. This study adopted the ensemble method to simulate the change in the river channel, with a single model combined with multiple parameters. The optimized parameter combinations for a given river reach are investigated. Two river basins, located in Taiwan, were used as study cases, to simulate river morphology through the SRH-2D, which was developed by the U.S. Bureau of Reclamation. The input parameters related to the sediment transport module were randomly selected within a reasonable range. The parameter sets with proper results were selected as ensemble members. The concentration of sedimentation and bathymetry elevation was used to conduct the calibration. Both study cases show that 20 ensemble members were good enough to capture the results and save simulation time. However, when the ensemble members increased to 100, there was no significant improvement, but a longer simulation time. The result showed that the peak concentration and the occurrence of time could be predicted by the ensemble size of 20. Moreover, with consideration of the bed elevation as the target, the result showed that this method could quantitatively simulate the change in bed elevation. With both cases, this study showed that the ensemble method is a suitable approach for river morphology numerical modelling. The ensemble size of 20 can effectively obtain the result and reduce the uncertainty for sediment transport simulation.

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Principles and approaches for numerical modelling of sediment transport in sewers

Water Science & Technology ◽

10.2166/wst.1995.0212 ◽

1995 ◽

Vol 31 (7) ◽

pp. 107-115 ◽

Cited By ~ 2

Author(s):

Ole Mark ◽

Cecilia Appelgren ◽

Torben Larsen

Keyword(s):

Mathematical Model ◽

Sediment Transport ◽

Numerical Modelling ◽

Simple Application ◽

Sewer Systems ◽

Sediment Deposits ◽

Model Mouse ◽

Modelling Approaches

A study has been carried out with the objectives of describing the effect of sediment deposits on the hydraulic capacity of sewer systems and to investigate the sediment transport in sewer systems. A result of the study is a mathematical model MOUSE ST which describes sediment transport in sewers. This paper discusses the applicability and the limitations of various modelling approaches and sediment transport formulations in MOUSE ST. Further, the paper presents a simple application of MOUSE ST to the Rya catchment in Gothenburg, Sweden.

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Hydrodynamic and Sediment Transport Simulation at The Port of The Electric Steam Power Plant Adipala and Serayu Estuary, Central Java Province, Indonesia

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/698/1/012006 ◽

2021 ◽

Vol 698 (1) ◽

pp. 012006

Author(s):

Nazariano Rahman Wahyudi ◽

Suntoyo ◽

Widi Agoes Pratikto

Keyword(s):

Sediment Transport ◽

Power Plant ◽

Steam Power ◽

Steam Power Plant ◽

Transport Simulation ◽

Central Java ◽

Central Java Province

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Sediment Transport and Water Flow Resistance in Alluvial River Channels: Modified Model of Transport of Non-Uniform Grain-Size Sediments

Water ◽

10.3390/w13152038 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2038

Author(s):

Gennady Gladkov ◽

Michał Habel ◽

Zygmunt Babiński ◽

Pakhom Belyakov

Keyword(s):

Sediment Transport ◽

Water Flow ◽

Transport Model ◽

Flow Characteristics ◽

Field Measurements ◽

Field Investigation ◽

Empirical Modeling ◽

River Channels ◽

Channel Deformations ◽

East European

The paper presents recommendations for using the results obtained in sediment transport simulation and modeling of channel deformations in rivers. This work relates to the issues of empirical modeling of the water flow characteristics in natural riverbeds with a movable bottom (alluvial channels) which are extremely complex. The study shows that in the simulation of sediment transport and calculation of channel deformations in the rivers, it is expedient to use the calculation dependences of Chézy’s coefficient for assessing the roughness of the bottom sediment mixture, or the dependences of the form based on the field investigation data. Three models are most commonly used and based on the original formulas of Meyer-Peter and Müller (1948), Einstein (1950) and van Rijn (1984). This work deals with assessing the hydraulic resistance of the channel and improving the river sediment transport model in a simulation of riverbed transformation on the basis of previous research to verify it based on 296 field measurements on the Central-East European lowland rivers. The performed test calculations show that the modified van Rijn formula gives the best results from all the considered variants.

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Estimating Heterogeneous Treatment Effects and the Effects of Heterogeneous Treatments with Ensemble Methods

Political Analysis ◽

10.1017/pan.2017.15 ◽

2017 ◽

Vol 25 (4) ◽

pp. 413-434 ◽

Cited By ~ 29

Author(s):

Justin Grimmer ◽

Solomon Messing ◽

Sean J. Westwood

Keyword(s):

Treatment Effects ◽

Ensemble Methods ◽

Ensemble Method ◽

Superior Performance ◽

Accurate Estimation ◽

Randomized Experiments ◽

Heterogeneous Treatment Effects ◽

Data Set ◽

Heterogeneous Effects ◽

The Ensemble Method

Randomized experiments are increasingly used to study political phenomena because they can credibly estimate the average effect of a treatment on a population of interest. But political scientists are often interested in how effects vary across subpopulations—heterogeneous treatment effects—and how differences in the content of the treatment affects responses—the response to heterogeneous treatments. Several new methods have been introduced to estimate heterogeneous effects, but it is difficult to know if a method will perform well for a particular data set. Rather than using only one method, we show how an ensemble of methods—weighted averages of estimates from individual models increasingly used in machine learning—accurately measure heterogeneous effects. Building on a large literature on ensemble methods, we show how the weighting of methods can contribute to accurate estimation of heterogeneous treatment effects and demonstrate how pooling models lead to superior performance to individual methods across diverse problems. We apply the ensemble method to two experiments, illuminating how the ensemble method for heterogeneous treatment effects facilitates exploratory analysis of treatment effects.

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Numerical modelling of sediment transport in open channel flows

Mechanics of Sediment Transport ◽

10.1201/9781003079019-23 ◽

2020 ◽

pp. 173-181

Author(s):

I. Çelik

Keyword(s):

Sediment Transport ◽

Numerical Modelling ◽

Open Channel ◽

Channel Flows ◽

Open Channel Flows

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B. River morphology & sediment transport

River Flow 2012 ◽

10.1201/b13250-8 ◽

2012 ◽

pp. 391-1015

Keyword(s):

Sediment Transport ◽

River Morphology

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SURVEY TECHNIQUES/PROCEDURES AND DATA PROCESSING FOR MONITORING NEARSHORE SEDIMENT TRANSPORT

Coastal Engineering Proceedings ◽

10.9753/icce.v18.97 ◽

1982 ◽

Vol 1 (18) ◽

pp. 97

Author(s):

J. Zacks

Keyword(s):

Sediment Transport ◽

Surf Zone ◽

Survey Techniques ◽

The Past ◽

Bed Elevation ◽

Innovative Methods ◽

Survey Error ◽

Nearshore Sediment Transport ◽

The Many ◽

The Cost

The cost of many coastal projects is often increased by the expensive beach repair and maintenance required to remedy the destabilising effects of structures on the adjoining coastline. Physical and/or mathematical models have been developed for use in planning these projects in order to predict and quantify the effects of marine sediment transport on the coastal topography. Such models need to be calibrated against prototype data and one method of gauging volumetric sediment movement is by successive bathymetric/ topographic profiting surveys which are performed seasonally and annually. Since large quantities of sediment are related to small changes in bed elevation it is clear that this profiling needs to be done with the utmost precision* The areas most affected extend from the beach through the surf zone to water depths of about 25 metres. The surf zone in particular is a dynamic and hostile area which falls outside the traditional activities of both the hydrographic and land surveyors. Consequently innovative methods, deficient in sound survey principle and practice, have often been pursued in this area without any attempt being made to assess the tolerance on the data. This paper attempts to show that it is possible to produce reliable and verifiable results to the required accuracy by using conventional survey equipment and techniques, also by taking the necessary precautions against the many possible sources of survey error. The procedures and techniques described have evolved from NRIO's involvement over the past decade in major projects at Richards Bay, Durban, Koeberg and in False Bay. The results of a recent verification investigation are fully reported in this paper.

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