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Prediction of discharge in a tidal river using the LSTM-based sequence-to-sequence models

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Acta Oceanologica Sinica 2024年第7期43卷 40-51页

作者： Zhigao Chen Yan Zong Zihao Wu Zhiyu Kuang Shengping Wang Key Laboratory of Mine Environmental Monitoring and Improving around Poyang Lake of Ministry of Natural Resources East China University of TechnologyNanchang 330013China School of Surveying and Geoinformation Engineering East China University of TechnologyNanchang 330013China

The complexity of river-tide interaction poses a significant challenge in predicting discharge in tidal *** short-term memory(LSTM)networks excel in processing and predicting crucial events with extended intervals and time delays in time series ***,the sequence-to-sequence(Seq2Seq)model,known for handling temporal relationships,adapting to variable-length sequences,effectively capturing historical information,and accommodating various influencing factors,emerges as a robust and flexible tool in discharge *** this study,we introduce the application of LSTM-based Seq2Seq models for the first time in forecasting the discharge of a tidal reach of the Changjiang river(Yangtze river)*** study focuses on discharge forecasting using three key input characteristics:flow velocity,water level,and discharge,which means the structure of multiple input and single output is *** experiment used the discharge data of the whole year of 2020,of which the first 80%is used as the training set,and the last 20%is used as the test *** means that the data covers different tidal cycles,which helps to test the forecasting effect of different models in different tidal cycles and different *** experimental results indicate that the proposed models demonstrate advantages in long-term,mid-term,and short-term discharge *** Seq2Seq models improved by 6%-60%and 5%-20%of the relative standard deviation compared to the harmonic analysis models and improved back propagation neural network models in discharge prediction,*** addition,the relative accuracy of the Seq2Seq model is 1%to 3%higher than that of the LSTM *** assessment of the prediction errors shows that the Seq2Seq models are insensitive to the forecast lead time and they can capture characteristic values such as maximum flood tide flow and maximum ebb tide flow in the tidal cycle *** indicates the significance of the Seq2Seq models.

关键词： discharge prediction long short-term memory networks sequence-to-sequence(Seq2Seq)model tidal river back propagation neural network Changjiang river(Yangtze river)Estuary

Hydrodynamic Characteristics and Sediment Transport of A tidal river Under Influence of Wading Engineering Groups

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China Ocean Engineering 2013年第6期27卷 829-842页

作者：陈珺唐洪武肖洋嵇敏 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University College of Dayu Hohai University

By taking the Yong river for example in this paper, based on the multiple measured data during 1957 to 2009, the change process of runoff, tide feature, tidal wave, tidal influx and sediment transport are analyzed. Then a mathematical model is used to reveal the influence mechanism on hydrodynamic characteristics and sediment transport of the wading engineering groups such as a tide gate, a breakwater, reservoirs, bridges and wharves, which were built in different periods. The results showed the hydrodynamic characteristics and sediment transport of the Yong river changed obviously due to the wading engineering groups. The tide gate induced deformation of the tidal wave, obvious reduction of the tidal influx and weakness of the tidal dynamic, decrease of the sediment yield of flood and ebb tide and channel deposition. The breakwater blocked estuarine entrances, resulting in the change of the tidal current and the reduction of the tidal influx in the estuarine area. The large-scale reservoirs gradually made the decrease of the Yong river runoff. The bridge and wharf groups took up cross-section areas, the cumulative affection of which caused the increase of tidal level in the tidal river.

关键词： hydrodynamic characteristics sediment transport wading engineering groups tidal river tide gate

AN ANALYSIS OF THE OXYGEN BALANCE IN AN ANOXIC tidal river

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Journal of Hydrodynamics 1994年第4期6卷 83-92页

作者： Joseph H. W. Lee, K. W. Choi (Department of Civil and Structural Engineering, University of Hong Kong)Chen Hui-guo Lin Ming-he(Environmental Sciences Research Centre, Zhongshan University, Guangzhou 510275, P. R. China) Department of Civil and Structural Engineering University of Hong Kong Hong Kong Environmental Sciences Research Centre Zhong.shan University Guangzhou 510275 China

A time-dependent, mixed-segment, slack tide oxygen balance model has been developed for the study of a heavily polluted tidal river discharging to a coastal *** and reaeration, BOD settling, benthal demand, freshwater flushing, and tidal mixing are the key processes modelled. Significant features of the model include the oxygen balance formulation under anoxic conditions and the tidal exchange condition at the seaward boundary. The simple model enables a clear and consistent interpretation of a set of dry season water quality data and an assessment of the assimilative capacity of the river is also made.

关键词： tidal river coastal bay water quality oxygen balance.

DEVELOPMENT OF COUPLED 1D-2D MATHEMATICAL MODELS FOR tidal riverS

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Journal of Hydrodynamics 2004年第6期16卷 767-776页

作者： XUZu-xin YINHai-long StateKeyLaboratoryofPollutionControlandResourceReuse TongjiUniversityShanghai200092.China

Some coupled 1D-2D hydrodynamic and water quality models depicting tidalwater bodies with complex topography were presented. For the coupled models, finite element methodwas used to solve the governing equations so as to study tidal rivers with complex topography. Sincethe 1D and 2D models were coupled, the principle of model coupling was proposed to accountappropriately for the factors of water level, flow and pollutant flux and the related dynamicalbehavior was simulated. Specifically the models were used to probe quantitative pollutioncontribution of receiving water from neighboring Jiangsu and Zhejiang Provinces to the pollution inthe Huangpu river passing through Shanghai City, Numerical examples indicated that the developedcoupled 1D-2D models are applicable in tidal river network region of Shanghai.

关键词： tidal river hydrodynamic water quality coupled model Huangpu river Shanghai

Seasonal variation of tidal prism and energy in the Changjiang river estuary： a numerical study

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Chinese Journal of Oceanology and Limnology 2016年第1期34卷 219-230页

作者：张敏 Ian Howard TOWNEND 蔡华阳周云轩 State Key Laboratory of Estuarine and Coastal Research East China Normal University Shanghai 200062 China Ocean and Earth Sciences University of Southampton Southampton SO171B J UK Department of Water Management Faculty of Civil Engineering and Geosciences Delft University of Technology Stevinweg 1 P.O. Box 5048 2600 GA Delft The Netherlands

tidal rivers are intrinsically complex because tidal propagation is influenced by river discharge. This study aims to examine the seasonal variation of tidal prism and energy variance in the tidal river of the Changjiang(Yangtze) river estuary in China. In order to quantify the behaviour of river and tide,we use numerical modelling that has been validated using measured data. We conduct our analysis by quantifying the discharge and energy variance in separate components for both the river and the tide,during wet and dry seasons. We note various definitions of tidal prism and explore the difference between tidal discharge on the flood and ebb and tidal storage volume. The results show that the river discharge attenuates the tidal motion and reduces the tidal flood discharge but the tidal storage volume is approximately constant with different riverine discharge since part of the fresh water discharge is intercepted and captured in the estuary due to the backwater effect. It appears that the tidal discharge adjusts according to the variation of river discharge to keep a constant tidal storage volume. An analysis of the hydraulics shows that the transition from tidal dominance(at the mouth) to river dominance(upstream) depends on the location of tidal current reversal which varies from wet season to dry season. Duringthe wet season,the Changjiang river estuary is totally dominated by energy from fresh water discharge.

关键词： hydrodynamics estuary convergence tidal prism hydraulics energy tidal river

Engineering application of submerged water jets for sediment removal in a tidal riverbed

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Water Science and Engineering 2022年第4期15卷 348-357页

作者： Chaiyuth Chinnarasri King Mongkut's University of Technology Thonburi Bangkok 10140Thailand

Sediment deposition problems have attracted the interest of engineers and *** experimental studies have been conducted on scour depth using turbulent ***,field observation and monitoring have rarely been *** study aimed to eliminate sediments on a tidal riverbed using a prototype device,which consisted of a set of submerged vertical water nozzles and submerged horizontal air *** effectiveness of the water jet in sediment removal during spring and neap tides was *** quantitative relationships of dimen-sionless parameters,such as(1)the relative sediment scour volume versus the number of flows from the jet exit,(2)the relative sediment scour volume versus the relative scour depth,and(3)the relative scour size versus the relative jet intensity,were *** results showed that the freshwater flowing to the sea affected the sediment scour volume during the falling cycle of spring *** contrast,the rising cycle of spring tides retarded the freshwater flow,resulting in a decrease in the sediment scour volume.A steep water surface slope accelerated the river flow and further influenced the cross-flow current around the study *** a result,a highly diffusive turbulent flow was produced,causing sus-pended sediments to be rapidly removed from the scour hole *** increase in the number of flows from the jets led to intensified diffusion of turbulent energy into the *** rapidly varying water depth caused jet energy to be dissipated before approaching the riverbed,and it significantly affected the scour process during the spring-tide *** proposed equations can be used to estimate the scour volume,scour size,and re-suspended sediments in tidal rivers within defined ranges of parameters.

关键词： Jet diffusion Scour hole Sediment re-suspension tidal river Field experiments

EXPERIMENTAL INVESTIGATIONS ON LONGITUDINAL DISPERSION CHARACTERISTICS OF tidal riverS

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Journal of Hydrodynamics 2003年第2期15卷 89-94页

作者： Fan Jing yu, Wang Dao zeng, Zhong Bao chang Shanghai Institute of Applied Mathematics and Mechanics, Shanghai University, Shanghai 200072, China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

The longitudinal dispersion characteristics of tidal rivers areexperimentally investigated in a water channel. The longitudinal dispersion features and influentialfactors on pollutant in various stages of a tidal period in natural rivers are studied; the valueranges and variation trends of the longitudinal dispersion coefficient are obtained by means ofconcentration measurement. The results can provide important parameters for establishing the waterquality mathematical models in tidal rivers.

关键词： tidal river diffusion longitudinal dispersion coefficient

MATHEMATICAL MODEL FOR 2-D tidal FLOW AND WATER QUALITY WITH ORTHOGONAL CURVILINEAR COORDINATES

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Journal of Hydrodynamics 2003年第5期15卷 103-108页

作者： LiuYu-ling WeiWen-li ShenYong-ming InstituteofwaterResourcesandHydroelectricEngineering Xi‘anUniversityofTechnologyXi’an710048China TheStateKeyLaboratoryofOceanOffshoreEngineering DalianUniversityofTechnologyDalian116023，China TheStateKeyLaboratoryofOceanOffshoreEngineering DalianUniversityofTechnologyDalian116023China

This paper presents a numerical method for simulating the 2-D tidal flow andwater quality with the orthogonal curvilinear coordinates. In order to overcome the computationaldifficulties in natural rivers, such as the complicated boundary figures, the great disparitybetween length and width of computational domain, etc. , orthogonal boundary-filled grid was *** irregular domain in physical plane was transformed into a rectangular domain in a transformedplane, and the depth-averaged momentum equations and mass equation were given and discretized basedon the alternating direction implicit finite difference scheme in curvilinear coordinates. Theapplication of the presented method was illustrated by an example of analyzing the Yangtze river inthe vicinity of Nanjing city. A fair agreement between the measured data and computed resultsdemonstrates the validity of the developed method.

关键词： orthogonal curvilinear coordinate boundary-fitted grid numerical simulationflow water quality tidal river

Sedimentary facies of the Silurian tide-dominated paleo-estuary of the Tazhong area in the Tarim Basin

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Petroleum Science 2008年第2期5卷 95-104页

作者： Zhang Jinliang Zhang Zhongjie College of Resource Science and Technology Beijing Normal University Beijing 100875 China School of Marine Geo-Science Ocean University of China Qingdao Shandong 266100 China

As the relative sea-level rose, a paleo-estuary was formed by the marine inundation of the braided river incised valley during the period of the lower sub-member of the upper member of the Kalpingtage. formation of the Silurian in the Tarim Basin, west China. Sandstone-mudstone rhythmite, tidal structures and bimodal cross-bedding are common in these deposits, indicating that tides played a significant role in generating the sedimentary structures and the estuary type was tide-dominated. Five depositional facies were grouped： tidal river, sandy and muddy subtidal flat, tidal flat, tidal bar, tidal channel on the basis of lithology, electric properties, rhythmicity, sedimentary structure, fossil and the contact relationship. The sediment distribution showing first fining seaward and subsequent coarsening seaward from head to mouth, implies the two sediment sources in the paleo-estuary. The paleo-estuary of the Tarim Basin is very different from other representative estuaries. The most important distinction is that there are two adjacent estuaries joined by tidal flat onshore and by sandy and muddy subtidal flat in the sea at the same time, while the others only architecture model for the tide-dominated estuary. have one, So the Tazhong paleo-estuary shows a good

关键词： Tarim basin Silurian tide-dominated estuary tidal river tidal bar