Pub Date : 2023-07-03DOI: 10.1080/21664250.2023.2233724
Pavitra Kumar, N. Leonardi
ABSTRACT As climate-driven risks for the world’s coastlines increase, understanding and predicting morphological changes as well as developing efficient systems for coastal forecast has become of the foremost importance for adaptation to climate change. Artificial Intelligence is a powerful technology that has been rapidly evolving recently and can offer new means of analysis for the coastal science field. Yet, the potential of these technologies for coastal geomorphology remains relatively unexplored with respect to other scientific fields. This article investigates the use of Artificial Neural Networks and Bayesian Networks in combination with fully coupled hydrodynamics and morphological models (Delft3D) for predicting morphological changes and sediment transport along coastal systems. Two sets of Artificial Intelligence models were tested, one set relying on localized modeling outputs or localized data sources and another set having reduced dependency from modeling outputs and, once trained, solely relying on boundary conditions and coastline geometry. The first set of models provides regression values greater than 0.95 and 0.86 for training and testing, respectively. The second set of reduced dependency models provides regression values greater than 0.84 and 0.76 for training and testing, respectively. Our results highlight the potential of AI and statistical models for coastal applications.
{"title":"Coastal forecast through coupling of Artificial Intelligence and hydro-morphodynamical modelling","authors":"Pavitra Kumar, N. Leonardi","doi":"10.1080/21664250.2023.2233724","DOIUrl":"https://doi.org/10.1080/21664250.2023.2233724","url":null,"abstract":"ABSTRACT As climate-driven risks for the world’s coastlines increase, understanding and predicting morphological changes as well as developing efficient systems for coastal forecast has become of the foremost importance for adaptation to climate change. Artificial Intelligence is a powerful technology that has been rapidly evolving recently and can offer new means of analysis for the coastal science field. Yet, the potential of these technologies for coastal geomorphology remains relatively unexplored with respect to other scientific fields. This article investigates the use of Artificial Neural Networks and Bayesian Networks in combination with fully coupled hydrodynamics and morphological models (Delft3D) for predicting morphological changes and sediment transport along coastal systems. Two sets of Artificial Intelligence models were tested, one set relying on localized modeling outputs or localized data sources and another set having reduced dependency from modeling outputs and, once trained, solely relying on boundary conditions and coastline geometry. The first set of models provides regression values greater than 0.95 and 0.86 for training and testing, respectively. The second set of reduced dependency models provides regression values greater than 0.84 and 0.76 for training and testing, respectively. Our results highlight the potential of AI and statistical models for coastal applications.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"450 - 469"},"PeriodicalIF":2.4,"publicationDate":"2023-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49064342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-06-29DOI: 10.1080/21664250.2023.2228005
T. Iwamoto, T. Takagawa, T. Shibayama, M. Esteban, Martin Mäll
ABSTRACT The actions of wind and atmospheric pressure associated with tropical cyclones (e.g. typhoons) are considered the primary factors behind the generation of storm surges, though the fields used in meteorological models can sometimes deviate from observations. To improve these, the direct modification method (DMM) has been previously proposed, though this only modifies the wind field of a typhoon, and further development is necessary for applying it to storm surge hindcasts. The present work describes the development of a semi-empirical gradient wind balance-based method (GWB-M) for modifying both the wind and pressure fields in meteorological models, based on the dynamic relationship between the wind and pressure in typhoons (i.e. gradient wind balance). The applicability of GWB-M was assessed through a storm surge hindcast based on Typhoon Faxai in 2019, which generated powerful waves and a storm surge at Tokyo Bay. GWB-M improved the time series of 10 m wind speed and sea level pressure, with their spatial distributions being more realistic than those in DMM and blending parametric typhoon models (BM), which cannot take into account the influence of the complex topography around Tokyo Bay. Further, the maximum sea level anomalies after the typhoon made landfall were also captured by GWB-M with a higher accuracy than DMM.
{"title":"A proposal of a semi-empirical method for modifying the atmospheric pressure and wind fields of tropical cyclones","authors":"T. Iwamoto, T. Takagawa, T. Shibayama, M. Esteban, Martin Mäll","doi":"10.1080/21664250.2023.2228005","DOIUrl":"https://doi.org/10.1080/21664250.2023.2228005","url":null,"abstract":"ABSTRACT The actions of wind and atmospheric pressure associated with tropical cyclones (e.g. typhoons) are considered the primary factors behind the generation of storm surges, though the fields used in meteorological models can sometimes deviate from observations. To improve these, the direct modification method (DMM) has been previously proposed, though this only modifies the wind field of a typhoon, and further development is necessary for applying it to storm surge hindcasts. The present work describes the development of a semi-empirical gradient wind balance-based method (GWB-M) for modifying both the wind and pressure fields in meteorological models, based on the dynamic relationship between the wind and pressure in typhoons (i.e. gradient wind balance). The applicability of GWB-M was assessed through a storm surge hindcast based on Typhoon Faxai in 2019, which generated powerful waves and a storm surge at Tokyo Bay. GWB-M improved the time series of 10 m wind speed and sea level pressure, with their spatial distributions being more realistic than those in DMM and blending parametric typhoon models (BM), which cannot take into account the influence of the complex topography around Tokyo Bay. Further, the maximum sea level anomalies after the typhoon made landfall were also captured by GWB-M with a higher accuracy than DMM.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"418 - 432"},"PeriodicalIF":2.4,"publicationDate":"2023-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45503082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-27DOI: 10.1080/21664250.2023.2217992
S. Pascolo, M. Petti, S. Bosa
ABSTRACT Predicting wind waves within confined and shallow basins is very important, given the decisive role they play in the resuspension mechanisms of sediments and nutrients from the bottom, on which the main morphological and environmental changes depend. Pascolo, Petti, and Bosa (2019) proposed a set of wave forecasting curves for fully developed conditions in finite depth, which consider the bottom roughness as an additional variable, since it plays a fundamental role in the wave energy dissipation during the generation process. The present study incorporates and integrates the results previously obtained by Pascolo, Petti, and Bosa (2019) and provides the growth curves in the complete form, taking into account also the limitation on fetch. A numerical approach on a simplified domain has been adopted and statistical analyses on the fit of the curves to numerical results have been performed. The new set of equations confirms the variability of the wave heights and periods as a function of the bottom conditions, which can change due to the presence of bedforms, vegetation, or particle size differences. Applications at different conditions of depth, fetch, and roughness have been analyzed, in order to confirm the validity of the new growth curves.
{"title":"New Fetch- and Depth-Limited Forecasting Curves Depending on Bed Roughness","authors":"S. Pascolo, M. Petti, S. Bosa","doi":"10.1080/21664250.2023.2217992","DOIUrl":"https://doi.org/10.1080/21664250.2023.2217992","url":null,"abstract":"ABSTRACT Predicting wind waves within confined and shallow basins is very important, given the decisive role they play in the resuspension mechanisms of sediments and nutrients from the bottom, on which the main morphological and environmental changes depend. Pascolo, Petti, and Bosa (2019) proposed a set of wave forecasting curves for fully developed conditions in finite depth, which consider the bottom roughness as an additional variable, since it plays a fundamental role in the wave energy dissipation during the generation process. The present study incorporates and integrates the results previously obtained by Pascolo, Petti, and Bosa (2019) and provides the growth curves in the complete form, taking into account also the limitation on fetch. A numerical approach on a simplified domain has been adopted and statistical analyses on the fit of the curves to numerical results have been performed. The new set of equations confirms the variability of the wave heights and periods as a function of the bottom conditions, which can change due to the presence of bedforms, vegetation, or particle size differences. Applications at different conditions of depth, fetch, and roughness have been analyzed, in order to confirm the validity of the new growth curves.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"394 - 417"},"PeriodicalIF":2.4,"publicationDate":"2023-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49089437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-22DOI: 10.1080/21664250.2023.2212860
T. Tsubono, Teruhisa Okada, Yasuo Niida, Yuya Kino, N. Nakashiki
ABSTRACT This paper proposes a generalized Green’s Function Approach (GFA) to calibrate the boundary conditions and parameters of a coastal current model. The GFA uses a pseudoinverse for the calculation of control variables, including the boundary conditions and parameters, and a Green’s function matrix, which is the response matrix of sensitivity experiments to the control variables. The GFA was applied to optimize tidal and tidal residual currents in a coastal region with a model simulating the thermal effluent discharged from a power plant. The GFA could be used robustly, regardless of the number of sensitivity analyses, and provided optimal increments for the control variables using a given threshold for the pseudoinverse. The optimization provided the appropriate sea surface conditions to reproduce tidal and tidal residual currents that were consistent with observations. The optimized model allowed an effective and accurate assessment of the environmental impact of the thermal effluent because tidal and tidal residual currents play an important role in the advection and diffusion of thermal effluent.
{"title":"Application of a generalized Green’s function approach to optimize modeled tidal and tidal residual currents for assessment of the dispersion area of thermal effluent discharges","authors":"T. Tsubono, Teruhisa Okada, Yasuo Niida, Yuya Kino, N. Nakashiki","doi":"10.1080/21664250.2023.2212860","DOIUrl":"https://doi.org/10.1080/21664250.2023.2212860","url":null,"abstract":"ABSTRACT This paper proposes a generalized Green’s Function Approach (GFA) to calibrate the boundary conditions and parameters of a coastal current model. The GFA uses a pseudoinverse for the calculation of control variables, including the boundary conditions and parameters, and a Green’s function matrix, which is the response matrix of sensitivity experiments to the control variables. The GFA was applied to optimize tidal and tidal residual currents in a coastal region with a model simulating the thermal effluent discharged from a power plant. The GFA could be used robustly, regardless of the number of sensitivity analyses, and provided optimal increments for the control variables using a given threshold for the pseudoinverse. The optimization provided the appropriate sea surface conditions to reproduce tidal and tidal residual currents that were consistent with observations. The optimized model allowed an effective and accurate assessment of the environmental impact of the thermal effluent because tidal and tidal residual currents play an important role in the advection and diffusion of thermal effluent.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"383 - 393"},"PeriodicalIF":2.4,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49206942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-05-14DOI: 10.1080/21664250.2023.2211793
D. Rathnayaka, Y. Tajima
ABSTRACT While a submerged breakwater has become one of the preferred options of shore protection structures because of its lower impact on the coastal landscape and environment, it causes complicated hydrodynamic characteristics and sometimes fails to meet the expected coastal protection functions. Accurate prediction of wave and current around the structure is therefore essential for appropriate design of a submerged breakwater. This study focused on the influence of the permeability of the submerged breakwater and newly conducted laboratory experiments using permeable and impermeable breakwaters. The model, Simulate WAves till SHore (SWASH), was then applied to these laboratory experiments and the difference of measured and computed wave and current field around the structure was investigated. It was found that the model qualitatively well represented the horizontal distribution of wave heights and phase-averaged current velocities although it overestimated the shoreward volume flux over the impermeable breakwater, but not over the permeable breakwater. Comparison of these contrasting results between permeable and impermeable breakwaters revealed that the phase-averaged bottom shear stress was underestimated on the crest of the impermeable breakwater. This feature highlighted the importance of the bottom friction forces accounting for the wave current coexisting field for better predictions of wave-induced current field around the submerged breakwaters.
{"title":"Influence of the permeability of submerged breakwaters on surrounding wave and current fields","authors":"D. Rathnayaka, Y. Tajima","doi":"10.1080/21664250.2023.2211793","DOIUrl":"https://doi.org/10.1080/21664250.2023.2211793","url":null,"abstract":"ABSTRACT While a submerged breakwater has become one of the preferred options of shore protection structures because of its lower impact on the coastal landscape and environment, it causes complicated hydrodynamic characteristics and sometimes fails to meet the expected coastal protection functions. Accurate prediction of wave and current around the structure is therefore essential for appropriate design of a submerged breakwater. This study focused on the influence of the permeability of the submerged breakwater and newly conducted laboratory experiments using permeable and impermeable breakwaters. The model, Simulate WAves till SHore (SWASH), was then applied to these laboratory experiments and the difference of measured and computed wave and current field around the structure was investigated. It was found that the model qualitatively well represented the horizontal distribution of wave heights and phase-averaged current velocities although it overestimated the shoreward volume flux over the impermeable breakwater, but not over the permeable breakwater. Comparison of these contrasting results between permeable and impermeable breakwaters revealed that the phase-averaged bottom shear stress was underestimated on the crest of the impermeable breakwater. This feature highlighted the importance of the bottom friction forces accounting for the wave current coexisting field for better predictions of wave-induced current field around the submerged breakwaters.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"369 - 382"},"PeriodicalIF":2.4,"publicationDate":"2023-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44474630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-04-03DOI: 10.1080/21664250.2023.2202958
T. Tazaki, E. Harada, H. Gotoh
ABSTRACT Sediment transport in the swash zone directly affects beach changes such as shoreline recession; thus, detailed understandings of sediment transport mechanisms are necessary to accurately estimate the short-time scales sediment transport rate. However, these detailed mechanisms under runup waves have not been elucidated because of the complex solid-gas-liquid multiphase turbulence flow. In this study, we attempt to numerically investigate the sediment grain-scale mechanism to overcome the shortcomings of experimental measurements and the free surface treatment in many numerical simulations. The gravel transport process on a sloped beach under regular waves was simulated using a 2D coupled model of the discrete element method (DEM) and a modified moving particle semi-implicit (MPS) method; a sub-model was built into the DEM-MPS model to improve fluid volume conservation. After validating the simulated performance by comparing it to a previous experiment, the gravel motions were investigated for turbulence and inner beach structure. The Shields number, estimated using the drag force distribution, revealed that significant turbulence contributed to onshore gravel transport near the rundown limit. The inter-gravel contact structure inside the beach explained the decrease in offshore sediment transport during backwash as increased resistance to gravel motions resulting from beach compaction.
{"title":"Grain-scale investigation of swash zone sediment transport on a gravel beach using DEM-MPS coupled scheme","authors":"T. Tazaki, E. Harada, H. Gotoh","doi":"10.1080/21664250.2023.2202958","DOIUrl":"https://doi.org/10.1080/21664250.2023.2202958","url":null,"abstract":"ABSTRACT Sediment transport in the swash zone directly affects beach changes such as shoreline recession; thus, detailed understandings of sediment transport mechanisms are necessary to accurately estimate the short-time scales sediment transport rate. However, these detailed mechanisms under runup waves have not been elucidated because of the complex solid-gas-liquid multiphase turbulence flow. In this study, we attempt to numerically investigate the sediment grain-scale mechanism to overcome the shortcomings of experimental measurements and the free surface treatment in many numerical simulations. The gravel transport process on a sloped beach under regular waves was simulated using a 2D coupled model of the discrete element method (DEM) and a modified moving particle semi-implicit (MPS) method; a sub-model was built into the DEM-MPS model to improve fluid volume conservation. After validating the simulated performance by comparing it to a previous experiment, the gravel motions were investigated for turbulence and inner beach structure. The Shields number, estimated using the drag force distribution, revealed that significant turbulence contributed to onshore gravel transport near the rundown limit. The inter-gravel contact structure inside the beach explained the decrease in offshore sediment transport during backwash as increased resistance to gravel motions resulting from beach compaction.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"347 - 368"},"PeriodicalIF":2.4,"publicationDate":"2023-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60334816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-29DOI: 10.1080/21664250.2023.2195030
Acacia Markov, J. Stolle, Ross Henteleff, I. Nistor, D. Pham Van Bang, E. Murphy, A. Cornett
ABSTRACT Physical modeling studies have endeavored to quantify the influence of plant biophysical parameters and hydrodynamics on wave-vegetation interactions and coastal protection. The accuracy with which such studies have characterized stem motion is limited by the predominant use of plant surrogates, and the few saltmarsh species considered in live vegetation studies. To address this, prototype-scale experiments were conducted in the outdoor Large Wave Canal of the Institut National de la Recherche Scientifique, Québec, in collaboration with the University of Ottawa and the National Research Council Canada, allowing novel characterization of live vegetation deformation under wave action. Two saltmarsh species were investigated (Spartina alterniflora, Spartina patens) under various irregular wave conditions (0.03 m< H s <0.28 m, T s 2.5, 10 s). Stem deformation was characterized using submerged cameras and bending angle tracking, coupled with wave height and velocity measurements. Significant differences in stem flexibility were observed between species, with S. alterniflora exhibiting more rigid stems (EI alterniflora =0.051 Nm2) than S. patens (EI patens =0.0015 Nm2; t-test; p<0.05). The two species consequexhibited different bending angles under similar hydrodynamic conditions, expected to influence their relative coastal protection capacity. These findings provide critical insight into the design of marsh construction or restoration for coastal protection.
摘要物理建模研究试图量化植物生物物理参数和流体动力学对波浪-植被相互作用和海岸保护的影响。这类研究描述树干运动的准确性受到植物替代物的主要使用以及活植被研究中考虑的少数盐沼物种的限制。为了解决这一问题，与渥太华大学和加拿大国家研究委员会合作，在魁北克国家科学研究所的室外大浪渠中进行了原型规模的实验，从而能够对波浪作用下的活植被变形进行新的表征。在各种不规则波浪条件下（0.03 m
{"title":"Deformation of Spartina patens and Spartina alterniflora stems under irregular wave action","authors":"Acacia Markov, J. Stolle, Ross Henteleff, I. Nistor, D. Pham Van Bang, E. Murphy, A. Cornett","doi":"10.1080/21664250.2023.2195030","DOIUrl":"https://doi.org/10.1080/21664250.2023.2195030","url":null,"abstract":"ABSTRACT Physical modeling studies have endeavored to quantify the influence of plant biophysical parameters and hydrodynamics on wave-vegetation interactions and coastal protection. The accuracy with which such studies have characterized stem motion is limited by the predominant use of plant surrogates, and the few saltmarsh species considered in live vegetation studies. To address this, prototype-scale experiments were conducted in the outdoor Large Wave Canal of the Institut National de la Recherche Scientifique, Québec, in collaboration with the University of Ottawa and the National Research Council Canada, allowing novel characterization of live vegetation deformation under wave action. Two saltmarsh species were investigated (Spartina alterniflora, Spartina patens) under various irregular wave conditions (0.03 m< H s <0.28 m, T s 2.5, 10 s). Stem deformation was characterized using submerged cameras and bending angle tracking, coupled with wave height and velocity measurements. Significant differences in stem flexibility were observed between species, with S. alterniflora exhibiting more rigid stems (EI alterniflora =0.051 Nm2) than S. patens (EI patens =0.0015 Nm2; t-test; p<0.05). The two species consequexhibited different bending angles under similar hydrodynamic conditions, expected to influence their relative coastal protection capacity. These findings provide critical insight into the design of marsh construction or restoration for coastal protection.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"325 - 346"},"PeriodicalIF":2.4,"publicationDate":"2023-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43325557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-21DOI: 10.1080/21664250.2023.2190002
Elad Dakar, J. M. Fernández Jaramillo, I. Gertman, R. Mayerle, R. Goldman
ABSTRACT We present a system for predicting the hourly significant wave height at a specific wave measurement station in the middle of Israel’s Mediterranean coast (Hadera). Our system uses an artificial neural network (ANN) composed of two sub-networks. We evaluate the importance of different inputs to the system. The input includes wind forecast data from the SKIRON atmospheric modeling system, wave forecast for the station’s location given by the SWAN wave model, and observed wave data. Our system pre-processes the wind data using a spatial filtering scheme and then enters it into the first sub-network in the form of a multidimensional tensor. We take special care to interconnect the tensor elements through a dimensional permutation that leads the ANN to sum elements along all the tensor’s dimensions. Our system groups the output of the first sub-network with the rest of the input and feeds it to the second sub-network that gives the prediction. Our ANN system outperforms the SWAN wave model in estimating wave heights over 1.5 meters. We obtain the best performance when either all input components are used or just wind and observations. Reimplementation of the system at Ashkelon yields smaller improvements due to insufficient training data.
{"title":"An artificial neural network based system for wave height prediction","authors":"Elad Dakar, J. M. Fernández Jaramillo, I. Gertman, R. Mayerle, R. Goldman","doi":"10.1080/21664250.2023.2190002","DOIUrl":"https://doi.org/10.1080/21664250.2023.2190002","url":null,"abstract":"ABSTRACT We present a system for predicting the hourly significant wave height at a specific wave measurement station in the middle of Israel’s Mediterranean coast (Hadera). Our system uses an artificial neural network (ANN) composed of two sub-networks. We evaluate the importance of different inputs to the system. The input includes wind forecast data from the SKIRON atmospheric modeling system, wave forecast for the station’s location given by the SWAN wave model, and observed wave data. Our system pre-processes the wind data using a spatial filtering scheme and then enters it into the first sub-network in the form of a multidimensional tensor. We take special care to interconnect the tensor elements through a dimensional permutation that leads the ANN to sum elements along all the tensor’s dimensions. Our system groups the output of the first sub-network with the rest of the input and feeds it to the second sub-network that gives the prediction. Our ANN system outperforms the SWAN wave model in estimating wave heights over 1.5 meters. We obtain the best performance when either all input components are used or just wind and observations. Reimplementation of the system at Ashkelon yields smaller improvements due to insufficient training data.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"309 - 324"},"PeriodicalIF":2.4,"publicationDate":"2023-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60334765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-10DOI: 10.1080/21664250.2023.2187740
Zhenfeng Zhai, Jie Li, Dan Liu, Jianming Miao
ABSTRACT The potential flow theory is used to develop a new analytical method to solve the diffraction problem of short-crested incident waves with uniform current acting on a concentric multiple-cylinder system. The influence of uniform current on the hydrodynamic performance of the concentric structure is discussed. The incident angle and speed of the currents have a significant influence on the short-crested wave force and run-up on the concentric structure, i.e. the wave force and wave run-up increase significantly when wave and uniform current directions are the same, while decreasing when in the opposite direction of the wave and uniform current. Additionally, the effects of parameters such as the current incidence angle, current speed, porous-effect parameters, number of perforated walls, and short-crestedness of regular waves on the hydrodynamic performance of the concentric structures are valuated by numerical experiments. It is observed that as the number of permeable walls increases, wave load on the impermeable internal cylinder gradually decreases and the wave surface around is more even. This study is expected to provide theoretical guidance for the design of nearshore architecture.
{"title":"Short-crested wave-current forces around a concentric multiple-cylinder structure","authors":"Zhenfeng Zhai, Jie Li, Dan Liu, Jianming Miao","doi":"10.1080/21664250.2023.2187740","DOIUrl":"https://doi.org/10.1080/21664250.2023.2187740","url":null,"abstract":"ABSTRACT The potential flow theory is used to develop a new analytical method to solve the diffraction problem of short-crested incident waves with uniform current acting on a concentric multiple-cylinder system. The influence of uniform current on the hydrodynamic performance of the concentric structure is discussed. The incident angle and speed of the currents have a significant influence on the short-crested wave force and run-up on the concentric structure, i.e. the wave force and wave run-up increase significantly when wave and uniform current directions are the same, while decreasing when in the opposite direction of the wave and uniform current. Additionally, the effects of parameters such as the current incidence angle, current speed, porous-effect parameters, number of perforated walls, and short-crestedness of regular waves on the hydrodynamic performance of the concentric structures are valuated by numerical experiments. It is observed that as the number of permeable walls increases, wave load on the impermeable internal cylinder gradually decreases and the wave surface around is more even. This study is expected to provide theoretical guidance for the design of nearshore architecture.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"295 - 308"},"PeriodicalIF":2.4,"publicationDate":"2023-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41738057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-25DOI: 10.1080/21664250.2023.2179791
P. Zheng, Ming Li, Jianting Du, Cai-xian Wang, J. Wolf, Xue'en Chen
ABSTRACT To conserve momentum flux across the air-sea interface, a new wind stress-wave-ocean coupled coastal model system is developed. Via simulating a specific idealized tropical cyclone (TC), this model is firstly applied to study the impacts of three wave effects, including the commonly studied wave-breaking induced acceleration, wave-enhanced bottom friction and the seldom studied wave modified surface stress (WMWS), and the conservation of momentum flux across air-sea interface (MFB) on the predictions of storm surge and inundation. It is then further applied to investigate the role of above four effects in modeling the peak surge and inundation by generalizing the TC forcing with various physical parameters, including the TC intensity, size, translation speed, and bottom slope. The model results reveal that WMWS can contribute considerably to the total surge height and inundation distance in a relatively high-intensity TC and its contribution depends weakly on the varying bottom slopes, TC sizes or translation speeds. By contrast, the MFB can only considerably reduce the maximum storm surge with a small bottom slope, while its reduction on inundation distance is more significant. The present study thus highlights the importance and necessity of incorporating the commonly ignored effects of WMWS and MFB in coastal modeling.
{"title":"Development of a fully coupled wind stress-wave-ocean coastal model system","authors":"P. Zheng, Ming Li, Jianting Du, Cai-xian Wang, J. Wolf, Xue'en Chen","doi":"10.1080/21664250.2023.2179791","DOIUrl":"https://doi.org/10.1080/21664250.2023.2179791","url":null,"abstract":"ABSTRACT To conserve momentum flux across the air-sea interface, a new wind stress-wave-ocean coupled coastal model system is developed. Via simulating a specific idealized tropical cyclone (TC), this model is firstly applied to study the impacts of three wave effects, including the commonly studied wave-breaking induced acceleration, wave-enhanced bottom friction and the seldom studied wave modified surface stress (WMWS), and the conservation of momentum flux across air-sea interface (MFB) on the predictions of storm surge and inundation. It is then further applied to investigate the role of above four effects in modeling the peak surge and inundation by generalizing the TC forcing with various physical parameters, including the TC intensity, size, translation speed, and bottom slope. The model results reveal that WMWS can contribute considerably to the total surge height and inundation distance in a relatively high-intensity TC and its contribution depends weakly on the varying bottom slopes, TC sizes or translation speeds. By contrast, the MFB can only considerably reduce the maximum storm surge with a small bottom slope, while its reduction on inundation distance is more significant. The present study thus highlights the importance and necessity of incorporating the commonly ignored effects of WMWS and MFB in coastal modeling.","PeriodicalId":50673,"journal":{"name":"Coastal Engineering Journal","volume":"65 1","pages":"277 - 294"},"PeriodicalIF":2.4,"publicationDate":"2023-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42326176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：