Article
Engineering, Ocean
Mehrshad Samadi, Mohammad Hadi Afshar, Ebrahim Jabbari, Hamed Sarkardeh
Summary: This study explores the use of data-driven methods to predict scour depth around pile groups, with MARS being the most accurate method and demonstrating the highest impact of parameters on scour depth.
MARINE GEORESOURCES & GEOTECHNOLOGY
(2021)
Article
Engineering, Marine
Haiyang Cheng, Yongzhou Cheng, Xiaoguang Wang, Bo Xia, Xing Lyu, Yuwei Zheng, Jing Zhang
Summary: Compared to vertical piles, the position relationship between the inclined pile and seabed has some extra effects on the surrounding wave-current interaction and sediment transporting mechanism. The magnitude relationship of relative scour depth (S/D) between the inclined and vertical piles will change visibly when the sand transporting capacity under wave-current action reaches a certain level.
Article
Engineering, Marine
Xuguang Chen, Xixi Liu, Hui Li, Fengpeng Zhang, Xian Zhang, Kehu Li
Summary: This study experimentally investigates the influence of different seabed geotechnical properties on the scour depth of piles, and establishes the scour mechanism and prediction equation. The results show that the scour depth decreases with an increase in relative densities of sand. The sand friction angle plays a dominant role in the scour mechanism, and seabed stress is positively correlated with relative density of sand. The seepage force of the sand has little effect on the scour depth of piles.
Article
Meteorology & Atmospheric Sciences
Nan Wang, Qin Chen, Ling Zhu, Hao Sun
Summary: A novel hybrid approach was developed by integrating a physics-based SWAN model with machine learning algorithms to predict wind waves in a shallow estuary. The study found that the hybrid approach (BRT-SWAN) can be an efficient tool for modelers to identify sources of error and calibrate parameters in physics-based models. Furthermore, the study showed that the hybrid approach achieved a similar level of accuracy to the approach trained with field observations of wind waves.
Article
Plant Sciences
Anil Akin, Ahmet Cilek, Ariane Middel
Summary: Quantifying urban tree cover is important, and this study used Sentinel-2 data and an Artificial Neural Network-Multi Layer Perception (ANN-MLP) approach to calculate and evaluate the factors driving the urban percent tree cover (PTC) in Bursa city, Turkey. The PTC was calculated using a Regression Tree (RT) analysis with several vegetation indices, and socio-economic, topographic, and biophysical variables were incorporated into the ANN-MLP approach. The results showed a high accuracy and correlation between the predicted ANN-MLP and observed tree cover maps, highlighting the importance of integrating remote sensing data and driving factors for accurate prediction of urban PTC.
URBAN FORESTRY & URBAN GREENING
(2023)
Article
Energy & Fuels
Haiyang Dong, Zhilin Sun, Shibiao Fang, Enshang Yang, Yun Pan
Summary: Accurate prediction of local scour depth is crucial for bridge safety. A series of experiments were conducted to obtain the prediction formula of local scour depth around pile groups. The results demonstrate that the scouring depth decreases in the flow direction, with the deepest scouring occurring in the first row of the upstream surface. The introduced calculation coefficient for pile group scour depth shows good agreement with measured values, indicating its rationality.
Article
Engineering, Marine
Shengtao Du, Guoxiang Wu, David Z. Zhu, Risheng Wang, Youxiang Lu, Bingchen Liang
Summary: Scour around submerged square piles in combined waves and current is a rarely studied phenomenon. This study conducted experimental tests in current-only conditions with different pile height-to-width ratios and fixed flow intensity. Results showed that the pile height-to-width ratio had a significant effect on scour depth, and the sediment scour rate was controlled by flow intensity in the initial scouring stage. In wave-current scour, the time needed to reach equilibrium scouring depth was much shorter than in current-only conditions due to sediment backfilling induced by sand ripples.
Article
Engineering, Civil
Negin Yousefpour, Steve Downie, Steve Walker, Nathan Perkins, Hristo Dikanski
Summary: This paper introduces three distinct methodologies for scour prediction using real-time monitoring data, including deep learning algorithms, ensemble neural networks, and calibrated empirical scour models based on Bayesian inference. These methods can predict bed elevation and water level variations as early as a week in advance, and forecast the maximum upcoming scour depth.
TRANSPORTATION RESEARCH RECORD
(2021)
Article
Engineering, Marine
Youxiang Lu, Bingchen Liang, Zegao Yin, Xinying Pan, Jun Wang, Shengtao Du
Summary: This study focuses on the importance of pile groups in long-term scour processes and how to predict them. Through flume experiments and data collection from literatures, an improved time factor is proposed, as well as another time factor for interpolation.
Article
Environmental Sciences
I. P. Senanayake, I. -Y. Yeo, J. P. Walker, G. R. Willgoose
Summary: This study tested downscaling algorithms based on the soil thermal inertia theory over a semi-arid agricultural landscape in Australia, showing promising results in integrating machine learning techniques for estimating near-surface soil moisture at a high spatial resolution.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Computer Science, Artificial Intelligence
Mostafa Boskabadi, Mahdi Doostparast
Summary: Neural networks and decision tree algorithms are essential tools in machine learning and data science, dealing with patterns among inputs and providing predictions for targets. This article proposes a hybrid approach that incorporates dependencies in regression trees and applies neural networks to terminal nodes. The approach allows for different weights in training neural networks across different terminal nodes, providing more flexibility when associations among inputs are observed. The performance of the approach is evaluated using real datasets and Monte-Carlo simulations in regression and classification problems.
NEURAL PROCESSING LETTERS
(2023)
Article
Engineering, Civil
Manish Pandey, Masoud Karbasi, Mehdi Jamei, Anurag Malik, Jaan H. Pu
Summary: In this research, experimental and computational investigations have been conducted to accurately predict the scour depth around the bridge abutment using three innovative ensemble-based data intelligence paradigms. A total of 308 series of laboratory data were used to develop the models, and the CatBoost model with Comb1 data input provided the best accuracy.
WATER RESOURCES MANAGEMENT
(2023)
Article
Construction & Building Technology
Nhat-Duc Hoang, Xuan-Linh Tran, Thanh-Canh Huynh
Summary: This study proposes a data-driven model that hybridizes machine learning and metaheuristic approaches to predict pile bearing capacity. Least squares support vector regression (LSSVR) is used to analyze a dataset containing historical records of pile tests, and opposition-based differential flower pollination (ODFP) metaheuristic is proposed to optimize the LSSVR learning process. Experimental results show that the proposed ODFP-optimized LSSVR achieves good predictive performance in terms of various error metrics.
ADVANCES IN CIVIL ENGINEERING
(2022)
Article
Agriculture, Multidisciplinary
Sukru Teoman Guner, Maria J. Diamantopoulou, Krishna P. Poudel, Aydin Comez, Ramazan Ozcelik
Summary: To ensure the sustainability of forest ecosystems, it is necessary to optimize forest management and develop accurate prediction methods for biomass. The Levenberg-Marquardt artificial neural network (LMANN) model is found to be the most flexible and accurate for predicting tree biomass data.
COMPUTERS AND ELECTRONICS IN AGRICULTURE
(2022)
Article
Engineering, Ocean
Xuguang Chen, Jinzhong Liu
Summary: This study investigates the effects of scour on rigid piles through scour tests under steady current and static lateral load tests. A three-dimensional scour hole model and its analytical expression suitable for engineering reality are proposed based on the results of scour tests. The results of load tests show that scour reduces the ultimate lateral capacity of foundations, with the reduction percentage related to the current direction but not affected by load eccentricity. Finally, a preliminary formula for evaluating the ultimate lateral capacity of rigid piles after scour is presented, providing a convenient and quick method to determine the upper and lower limits of scour effects.
APPLIED OCEAN RESEARCH
(2022)
Review
Engineering, Ocean
Ali Koosheh, Amir Etemad-Shahidi, Nick Cartwright, Rodger Tomlinson, Marcel R. A. van Gent
Summary: This paper reviews the design criterion for coastal structures regarding allowable mean overtopping discharge, as well as the study of individual wave overtopping including estimation of overtopping probability, statistical methods, and temporal evolutions of overtopping flow thickness/velocity. Additionally, it discusses common experimental measurement and data analysis techniques with a focus on their advantages and limitations.
APPLIED OCEAN RESEARCH
(2021)
Article
Engineering, Civil
Amir Etemad-Shahidi, Meysam Bali, Marcel R. A. van Gent
Summary: The importance of toe design for coastal engineers is highlighted, along with the current research status regarding experiments and formulas used to study toe stability. A new stability formula is developed based on physical reasoning and regression analysis, outperforming existing formulas and providing design hints for practitioners.
COASTAL ENGINEERING
(2021)
Article
Energy & Fuels
Ophelie Choupin, Michael Henriksen, Amir Etemad-Shahidi, Rodger Tomlinson
Summary: Wave energy converters (WECs) are crucial in the transition towards a more renewable-based energy mix, but cost information is often limited and there is a lack of flexible cost breakdown methods. This study compares different costing methods and introduces a more flexible and generic CapEx method, showing that factors identified could represent up to 30% of the cost.
Article
Engineering, Civil
Mohammed Al-Ogaili, Amir Etemad-Shahidi, Nick Cartwright, Sigurdur Sigurdarson
Summary: The study highlighted the importance of berm recession in the design and assessment of berm breakwaters, with different recession formulas showing varying performances. The stability number was found to be the significant parameter influencing recession, but there was inconsistency regarding the influence of T0 on recession amongst the formulas. Some formulas performed better in predicting recession, such as Sigurdarson and Van der Meer (2013) formula, showing better accuracy in this case.
COASTAL ENGINEERING
(2022)
Article
Engineering, Civil
Ali Koosheh, Amir Etemad-Shahidi, Nick Cartwright, Rodger Tomlinson, Marcel R. A. van Gent
Summary: This study investigates the wave overtopping rate at rubble mound seawalls through physical model tests and proposes a new formula which significantly improves prediction accuracy compared to existing empirical formulae.
COASTAL ENGINEERING
(2022)
Article
Engineering, Civil
Amin Reza Zarifsanayei, Jose A. A. Antolinez, Amir Etemad-Shahidi, Nick Cartwright, Darrell Strauss
Summary: This paper investigates the uncertainty of longshore sediment transport (LST) rates along a non-straight coastline using an ensemble modeling framework. The results show that the uncertainty of LST rates is higher for open coasts compared to semi-sheltered coasts, with the choice of wave transformation methods being a major factor in the annual uncertainty.
COASTAL ENGINEERING
(2022)
Article
Environmental Sciences
Amin Reza Zarifsanayei, Jose A. A. Antolinez, Amir Etemad-Shahidi, Nick Cartwright, Darrell Strauss, Gil Lemos
Summary: This study quantifies uncertainties in potential longshore sediment transport (LST) rate changes along a non-straight coastline. The study addresses four main sources of uncertainty, including emission scenarios, Global Circulation Model-driven offshore wave datasets, LST models, and their interactions. Two ensemble modelling frameworks are used to analyze these uncertainties. The results show that bias correction can reduce the range of uncertainty in LST projections. However, no robust projected changes in LST rates on annual and seasonal scales were found.
FRONTIERS IN MARINE SCIENCE
(2022)
Correction
Engineering, Civil
Amir Etemad-Shahidi, Meysam Bali, Marcel R. A. van Gent
COASTAL ENGINEERING
(2022)
Article
Engineering, Environmental
Mohammad Hassan Ranjbar, David P. Hamilton, Amir Etemad-Shahidi, Fernanda Helfer
Summary: This study investigates the impact of atmospheric stilling on the distribution of Microcystis blooms. The results highlight the importance of considering dynamic variations in colony size for accurate prediction of cyanobacterial bloom development and decay. The findings suggest that atmospheric stilling needs to be included in projections of changes in the frequency, distribution and magnitude of blooms of buoyant, colony-forming cyanobacteria under climate change.
Article
Engineering, Civil
Amir Etemad-Shahidi, Ali Koosheh, Marcel R. A. van Gent
Summary: This study focuses on improving the formula for the mean overtopping discharge in rubble mound structures by considering the physics of the process. A simple and superior formula was developed, evaluated against existing ones, and design guidelines were provided for practitioners.
COASTAL ENGINEERING
(2022)
Article
Engineering, Civil
Ali Koosheh, Amir Etemad-Shahidi, Nick Cartwright, Rodger Tomlinson, Marcel R. A. van Gent
Summary: This study contributes to the knowledge of individual overtopping volumes and the estimation of maximum volume (Vmax) in rubble mound seawalls. Through small-scale physical model tests and statistical analysis, weighted methods were found to be superior in estimating Vmax, reducing scatter index values by 23% and 17% compared to existing methods. Additionally, a simple empirical formula was developed for Vmax estimation, outperforming distribution-based methods and existing formulas.
COASTAL ENGINEERING
(2022)
Correction
Engineering, Civil
Saeed Shaeri, Amir Etemad-Shahidi
COASTAL ENGINEERING
(2022)
Review
Energy & Fuels
Shabnam Hosseinzadeh, Amir Etemad-Shahidi, Rodney A. Stewart
Summary: Growing energy demand worldwide has led to increased interest in offshore renewable energy exploitation. Combining wind and wave energy can result in stable power output at a lower cost. Identifying optimal locations for offshore renewable energy farms is crucial.
Article
Engineering, Marine
Meysam Bali, Amir Etemad-Shahidi, Marcel R. A. van Gent
Summary: Slope stability formulae for rubble mound structures are usually developed for head-on conditions. The effect of oblique waves is often neglected, but it can result in a reduction in required armour size. This study aims to develop a suitable wave obliquity reduction factor for the stability formula and demonstrates an improved stability prediction using this factor.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Environmental Sciences
Amin Reza Zarifsanayei, Jose A. A. Antolinez, Nick Cartwright, Amir Etemad-Shahidi, Darrell Strauss, Gil Lemos, Alvaro Semedo, Rajesh Kumar, Mikhail Dobrynin, Adem Akpinar
Summary: Four experiments were conducted to investigate uncertainty in future longshore sediment transport (LST) projections, including working with continuous or sliced time series of waves, different wave-model-parametrization pairs, and the inclusion/exclusion of sea level rise (SLR) for wave transformation. The results showed that the uncertainty in LST projections depends on model selection, climate variability, wave parameterization schemes, and the inclusion of SLR. The study also found that CMIP6 and CMIP5 driven wave climatology yield similar outcomes, and that the variability of LST rates is influenced by the parameterization schemes of the wave simulations.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Engineering, Ocean
Canjun Yang, Dingze Wu, Puzhe Zhou, Shuyang Ma, Rui Zhou, Xin Zhang, Yang Zhang, Qingchao Xia, Zeliang Wu
Summary: The Argo Global Ocean Observing Network is the preeminent ocean observation network worldwide, but its buoys fail to complete long-term observations in designated sea areas due to their lack of lateral movement. To solve this problem, a portable underwater profiler (PUP) that combines buoy and underwater glider functionalities was developed. The PUP is lightweight, allows for rapid deployment, and enables continuous observation.
APPLIED OCEAN RESEARCH
(2024)
Article
Engineering, Ocean
Knut Andreas Kvale, Bernt Leira, Ole Oiseth
Summary: As future floating bridges become longer, the chance of encountering significant inhomogeneous wave conditions increases. This paper presents an approach to model these conditions using generalized harmonic decomposition and applies it to a conceptual floating bridge model in Norway. The paper focuses on frequency-domain simulation and highlights the importance of considering the coherency in swell sea conditions.
APPLIED OCEAN RESEARCH
(2024)
