bluuebunny/crossref_metadata_2025 huggingface dataset:
STUDY OF DETERMINING RISK LEVEL REGARDING SWIMMING CONDITION ON BATHING BEACH USING AI
Authors: Toguchi Haruki , Shimada Ryo , Ishikawa Toshinori , Komine Tsutomu
Published: September 2023

In Japan, 2,000 to 3,000 drowning accidents occur every summer season at major bathing beaches. In order to prevent drowning accidents, beachgoers themselves need to be aware of the dangers and avoid them. As a way to do this, bathing beaches provide daily risk levels regarding swimming conditions to beachgoers using three levels of beach safety flags. However, the risk levels are determined subjectively and empirically by lifesavers and beach administrators based on weather and sea conditions. The characteristics of past drowning accidents are not taken into account. In this study, we suggest an objective method of determining the risk levels based on the probability of drowning accidents. We have created an AI model that can predict the probability of drowning accidents with high accuracy using a total of 53 features such as usage, weather and sea conditions of a study beach in Japan. This method enables appropriate judgment of swimming conditions to prevent many drowning accidents. The reliability of the model was examined using XAI, and it was found that time series of rescue factors were important in predictions. On the other hand, the accuracy decreased when the created AI model was applied to other beaches. It was thought to be caused by differences in the natural environment such as waves and wind.
ESTUARINE-WIDE SEDIMENT DYNAMICS UNDER HUMAN INTERVENTIONS AND CLIMATE CHANGE EFFECTS; AN IDEALISED MODEL STUDY
Authors: Siemes Rutger , Duong Trang Minh , Willemsen Pim , Borsje Bas , Hulscher Suzanne
Published: September 2023

Estuaries worldwide are under constant anthropogenic pressure. They are susceptible to climate change effects, from the sea (sea level rise, changing wave climate) and from the river-side (changing river discharge). Besides, estuaries are channelised and embanked to improve flood safety and to reclaim land, and channels are deepened to allow bigger ships to enter the ports. To optimise estuarine functions and sustainably prepare for future challenges, improved understanding of estuarine sediment dynamics after potential changes in the systems configuration and forcings is desired. This paper aims to assess the annual sediment dynamics of an estuary under a climate change effects, and how this is affected by human interventions.
EQUILIBRIUM MORPHOLOGY MODEL APPLIED THROUGHOUT THE EXTENSIVE NAVIGATION CHANNEL NETWORK OF THE GOLD COAST WATERWAYS, AUSTRALIA
Authors: Nielsen Jesper , Ware Dan , Karatvuo Helena , Mortensen Simon
Published: September 2023

The prediction of sedimentation in waterways can preempt navigational hazards and support ongoing maintenance operations. The NCOS online software (Mortensen et al, 2018), used by port operators globally, has recently been upgraded to include the capability to predict sedimentation. This paper introduces the elegant but powerful equilibrium morphology model which would otherwise remain “behind the scenes” in the software.
PROBABILISTIC APPROACHES FOR ASSESSING EROSION HAZARD ALONG NEW SOUTH WALES MID NORTH COAST
Authors: Thomson Michael , Rodger Daniel , Pender Doug
Published: September 2023

A probabilistic shoreline hazard assessment has been undertaken for the Clarence Valley coastline on the Mid North Coast of New South Wales. The assessment was unique in its size and scope, implementing a detailed probabilistic methodology that spanned 70km of varying coastline, including a range of open coasts, embayed beaches, multiple headlands, river training walls, sand sources and sinks. It was designed to meet the requirements of the NSW Management Manual, for inclusion within an updated Coastal Management Program.
SATELLITE DERIVED BATHYMETRY FOR MONITORING NEARSHORE DYNAMICS
Authors: Kras Etiënne , Luijendijk Arjen , Donchyts Gennadii , Santinelli Giorgio , Langemeijer Jaap , Gwee Robyn , Rodenas Antonio Moreno
Published: September 2023

Research on the physical, ecological, and environmental processes in the coastal zone traditionally rely on the availability of accurate seafloor topography (bathymetry) information. This information becomes increasingly important as coastal environments are under pressure by climate change and anthropogenic developments. Nonetheless, the bathymetry of shallow nearshore waters is only marginally monitored by cost- and time-intensive survey techniques that are dependent on in-field environmental conditions. Here, Satellite Derived Bathymetry (SDB) offers a valuable alternative to enrich available bathymetric data in both data sparse and data rich environments, reducing the need for in-situ measurements in the future. The high spatial and temporal resolution of satellite imagery yields a more comprehensive understanding of our coast and its dynamics. Yet, consistently mapping temporal change is still challenging, as the majority of currently available empirical SDB algorithms are heavily dependent on in-situ data for calibration purposes. In this study we present a methodology for assessing nearshore horizontal morphodynamics using the uncalibrated reflectance signal from satellite sensors while focusing on the Friese Zeegat, a tidal inlet of the Dutch Wadden Sea.
EFFECT OF LARGE-SCALE FORCING ON THE LOCAL SEDIMENT TRANSPORT POTENTIAL AT THE SCHLESWIG-HOLSTEIN BALTIC SEA COAST
Authors: Dissanayake Pushpa , Winter Christian , Averes Tanita , Krämer Knut , Sone Htun , Dreier Norman , Nehlsen Edgar , Fröhle Peter , Hirschhäuser Thomas
Published: September 2023

The Schleswig-Holstein (SH) Baltic Sea coast consists of different morphological features (e.g., bars, beaches, dunes, cliffs), which are continuously shaped by various along- and cross-shore sediment transport patterns driven by local currents generated from tides, seiches, winds and waves (Soomere et al., 2012). Understanding local scale sediment transport is of utmost importance to manage the scarce coastal sediments and to identify suitable mitigation strategies against extreme forcing scenarios (Hofstede and Hamann, 2022). This investigation was carried out at the exemplary cliff coast at Stohl, at which the glacial till cliff (maximum height about 20 m) is the source of nearshore sediments (Averes et al., 2021). The main objective of this study is to investigate the relative importance of different forcing conditions on local sediment transport pathways.
SATELLITE-DERIVED SANDY SHORELINE CHANGE (1984-2020) AND PRIMARY DRIVERS IN SW FRANCE
Authors: Castelle Bruno , Ritz Auguste , Marieu Vincent , Lerma Alexandre Nicolae , Vandenhove Marine
Published: September 2023

Sandy shoreline erosion has become one of the biggest threats to coastal zones globally, both in developed and less developed regions of the world, which calls for improved understanding of past and future shoreline evolution and its drivers. This is true for long-term shoreline change trends but also for interannual shoreline response linked to largescale climate patterns of atmospheric variability, which so far has been mostly explored locally based in situ monitoring program (e.g. Dodet et al., 2019). Free-of-charge publicly available optical satellite imagery can now be used to provide short-term to multi-decadal shoreline data from the local to the global scale using different techniques (e.g., Bishop-Taylor et al., 2019), with errors typically under 10 m at microtidal beaches (Vos et al., 2019). However, on high-energy and/or meso to macrotidal low-gradient beaches satellite-derived shoreline (SDS) errors dramatically worsen (Castelle et al., 2021). In this contribution we explore if an adapted space-averaging of such uncorrected (noisy) SDS dataset can allow addressing the time- and space variability of shoreline change and their primary drivers including large-scale climate patterns of atmospheric variability.
THE EVOLUTION TREND OF A BEACH IN CONSEQUENCE OF THE BUILDING OF COASTAL STRUCTURES
Authors: Filianoti Pasquale , Gurnari Luana
Published: September 2023

The shoreline deformation produced by the interaction between waves and coastal structures have been analyzed by comparing two different analytical solutions. Starting from the same assumption, they converge to different profiles, according to the different way to take in account the phenomenon of the wave diffraction induced by the structure.
SATELLITE-DERIVED SHORELINE DYNAMICS AT THE GERMAN BALTIC SEA
Authors: Tiede Jan , Jordan Christian , Schlurmann Torsten
Published: September 2023

Dunes play a central role in the coastal protection strategy of the German part of the Baltic Sea coastline in the state of Mecklenburg Western Pomerania (MWP). Considering the sea level rise and the limited supply of sand a closer inspection of the sand nourishment strategy and its impact on the regional shoreline of MWP is needed. Data availability on the shoreline development is sparse and only recently have the authorities (StALU) in MWP started to increase the temporal and spatial resolution of measurements (StALU 2009). The Google Earth Engine (Gorelick et al. 2017) has facilitated the possibility to investigate shorelines at the planetary scale with freely available satellite images spanning more than 30 years. Luijendijk et al. (2018) and Bishop-Taylor et al. (2021) have demonstrated the need and feasibility of long-term time series that depict the shoreline development over large spatial scales. We present the results from the remote sensing of the shoreline development at the German Baltic Sea utilizing three decades of satellite images.
GRASS SOD PULLING TESTS TO DETERMINE RESISTANCE AGAINST EROSION BY WAVE OVERTOPPING
Authors: Steendam Gosse Jan , Meer Jenttsje van der , Mom André van Hoven, Roy
Published: September 2023

From 2007 wave overtopping tests with the Wave Overtopping Simulator (Van der Meer et al, 2008) have been performed on real dikes in order to determine the strength of grass covers against loads from wave overtopping. Over 15 different locations and over 50 different test sections have been tested. Most of these large scale tests have been performed on grass covers on a clay subsoil. As part of the tests since 2014, grass pull tests with a grass sod pulling device have been performed in order to estimate the critical velocity, the strength of the grass cover, on a specific subsoil with a small and easy to perform test. The critical velocity is derived from the critical normal stresses which are calculated from the force needed to pull out the grass sod and the dimensions of the pulled sod. The method of determining the critical velocity from grass pull tests has been validated with the results of tests with the Wave Overtopping Simulator. The practical, mobile and easy to perform grass pull tests can be used to evaluate the strength of grass covers over time after seeding and for an estimation of strength of existing grass covers on different subsoils.
EFFECT OF TSUNAMI INDUCED CURRENTS ON FLOATING PONTOONS WITH THE MOORING LINES
Authors: Ozbahceci Berguzar Oztunali , Celik Hilal , Girgin Elif , Yalciner Ahmet Cevdet , Gozde Guney Dogan
Published: September 2023

A strong earthquake (Mw=6.6) of normal faulting striking about E-W occurred on October 30, 2020, between offshore Seferihisar (Izmir, Turkey) and Samos Island (Greece). The earthquake generated a tsunami that affected a region in the Aegean Coast of Turkey from Cesme Alacati in the northwestern part to Gumuldur coast in the southeastern part. The tsunami caused a change in the sea water level, inundations, and severe damage to marine vessels and coastal structures. Especially, floating docks in Teos Marina, Seferihisar were highly damaged due to tsunami hydrodynamic forces (GEER, 2020). It was observed that the mooring chains and fairleads were broken, and the pontoons were dragged offshore. Moreover, the aluminum frames of docks and the moored ships were damaged. The literature survey shows that although the effect of tsunami-induced currents on the floating docks with pile guides is investigated (Keen et al. 2017), there is not any study that calculates damages on the floating docks with connected units and the mooring lines and the assessment of the damage due to the tsunami-induced currents using a hydrodynamic numerical model. In this study, the effect of tsunami-induced sea-level changes and currents on the floating docks of Teos Marina are investigated by numerical hydrodynamic modeling.
PROGRESSION OF MEAN DAMAGE ON A MOUND BREAKWATER IN ITS SERVICE LIFE
Authors: Santamaría Miguel , Clavero María , Losada Miguel A.
Published: September 2023

Because of the expected sea level rise, most of the human properties located on the coast have to be protected during the present century. One of the engineering alternatives is to build rock sloping coastal structures. Currently, their design has to include procedures for aging and deteriorating to forecast their maintenance and reparation costs during its service life. The objective of the present research is to reformulate the rate of mean damage proposed by Melby and Kobayashi (1998) to predict the progression of mean damage, S, on a given mound breakwater typology under sequences of storms with varying wave conditions and water levels. The proposal is based on the interplay of water depth, h, incident significant wave height, Hs and mean wave period, Tm at the toe of the slope, and the impinging number of waves, Nw (Losada et al. (2021)).
EROSION MITIGATION DESIGN IN THE ARCTIC CONSIDERING CLIMATE CHANGE IMPACTS
Authors: Scott Fred , Duckett Fiona , Arenson Lukas , Klengenberg Charles , Elias Erwin
Published: September 2023

The Hamlet of Tuktoyaktuk is a low-lying peninsula in the Arctic on the Beaufort Sea that is vulnerable to coastal erosion and intermittent flooding. Most residences and buildings located near the coast have been relocated; those remaining are currently at risk of damage or destruction during storm events. In the longer term, cultural sites such as the graveyard are also at risk. Nearby Tuktoyaktuk Island, a beach/bluff system which shelters Tuktoyaktuk Harbour from waves, is eroding and if not protected may be gone by 2050. Baird was retained by the Hamlet of Tuktoyaktuk and Inuvialuit Regional Corporation (IRC) to assess erosion mitigation alternatives and select/implement a preferred design to protect the Hamlet and Island, which comprise a total shoreline length of approximately 2 km. Baird developed three design alternatives for shoreline protection, including articulated concrete block mattress (ACBM), concrete slab, and quarried armour stone revetments. The selected design is comprised of a quarried armour stone revetment along the entirety of the exposed shoreline of Tuktoyaktuk Island and the majority of the Tuktoyaktuk Hamlet shoreline.
EXPERIMENTAL INVESTIGATIONS INTO THE EFFECT OF STRONG WINDS ON WAVE OVERTOPPING AT A VERTICAL SEAWALL
Authors: Inagaki Naoto , Shibayama Tomoya , Ishibashi Kunihiko , Nakamura Ryota , Esteban Miguel
Published: September 2023

Given the possible future intensification of tropical cyclones as a consequence of ongoing global warming, it is becoming increasingly important to consider the effect that stronger winds will have on nearshore wave dynamics. Despite the possible influence of wind on the characteristics of wave overtopping having been suggested decades ago (e.g. Iwagaki et al., 1966), to the authors’ knowledge, not so many studies on wave dynamics have discussed this effect (e.g. Ward, 1998). Hence, the present study quantitatively analyses the overtopping of coastal structures under various types of waves and wind speeds, and will discuss the wind effects on elementary hydrodynamic processes such as wave breaking.
TSUNAMI FLOW PARAMETERS INFLUENCING PORT DAMAGE: A CASE-STUDY OF THE 2011 TOHOKU TSUNAMI
Authors: Chua Constance Ting , Pakoksung Kwanchai , Suppasri Anawat , Switzer Adam
Published: September 2023

In the past decade, tsunami fragility models have emerged as a common way of quantifying the relationship between tsunami flow characteristics and structural vulnerability. Fragility functions describe the probability that a structure exceeds a prescribed damage threshold for a given tsunami intensity. Tsunami flow characteristics are represented by tsunami intensity measures (hereafter referred to as TIM) in fragility modelling. The use of an appropriate TIM is imperative to deriving models with as much accuracy as possible. This aspect of research is still an area of debate. In this study, the aim is to assess TIMs that are most optimal for the estimation of structural fragility of port structures. The 2011 Tohoku tsunami was selected as our case study, and we use the damage data for port structures obtained from Chua et al. (2021). We investigate the relationship between three TIMs – depth, velocity and hydrodynamic drag force, and structural response.
A CLOSED-FORM SOLUTION FOR INTERACTIONS BETWEEN WAVES AND AN ARRAY OF FISH NET CAGES
Authors: Ma Mingyuan , Zhang Hong , Jeng Dong-Sheng , Wang Chien Ming
Published: September 2023

Understanding the multi-cage interaction mechanism in fish cage arrays and the hydrodynamic behaviour of cage structures will help engineers explore the feasibility of offshore fish farming. In this study, a semi-analytical method is developed to simulate the wave response of an array of cylindrical fish cages with arbitrary layouts and dimensions, including the wave interference effects among the multiple cages. By eigenfunction expansions, the general solution of the present research problem is expressed in the form of a Fourier-Bessel series, and the corresponding particular solution is obtained by introducing relevant boundary conditions and the least-squared method. The simulation results show that significant wave effects occur at the top of the cages, and the dynamic response of each cage has obvious phase differences. Parametric studies on the wave forces show that the wave force is zero at a specific wave frequency and the wave forces are decreased under high porosity nets.
STABILITY OF RUBBLE MOUND STRUCTURES UNDER OBLIQUE WAVE ATTACK
Authors: Bali Meysam , Etemad-Shahidi Amir , Gent Marcel R.A. van
Published: September 2023

Stability formulae for armour layers of rubble mound breakwaters are generally developed for perpendicular wave attack and do not include effects of oblique waves. Waves usually attack breakwater obliquely as the sea wave is three dimensional. Several studies have been performed to investigate the effect of wave angle (beta) on the armor stability. Galland (1994), Yu et al. (2002), Wolters and Van Gent (2010) and van Gent (2014) performed laboratory experiments to consider effects of oblique waves on the stability of armour layers. They performed tests with long-crested and/or short-crested waves on rock and concrete armours. The aim of this study is to find an appropriate and compatible reduction factor for EBV stability formulae.
WAVE TRANSFORMATION ON CORAL REEFS: COMPARISON OF A CFD MODEL AND PHYSICAL MODEL TESTS OF A MALDIVIAN REVETMENT
Authors: Mik-Meyer Villy L. , Schløer Signe , Bergøe Tony Erik
Published: September 2023

Designing optimized coastal structures on islands bordered by coral reefs has proven to be a challenging task due to the complex reef and wave interaction (Jensen, 1991; Jensen, Sloth and Jacobsen, 1998). Often the reefs in these tropical regions have a steep seaward profile until a certain depth, whereafter the reef suddenly becomes flat with a mild slope. When offshore waves reach the reef, it can result in plunging wave breaking, a wave set-up, and energy transfer from the peak frequency to lower frequencies resulting in long period wave motions. Under these conditions, it is difficult to predict the rate of overtopping as the complex hydrodynamics are not covered in standard overtopping formulas. Furthermore, the standard spectral wave models, on which the overtopping formulas often are based, cannot describe the transformation of offshore waves over the reef as the models are not able to resolve the physics of this violent water motion. In connection with the hydraulic study for a detailed design of a revetment on Fuvahmulah in the Maldives, the OpenFOAM CFD model is applied to obtain the hydrodynamic design parameters. The wave dynamics on the reef, the revetment overtopping rates, and hydrodynamic forces derived from the numerical model are compared with results from a physical model conducted by the Danish Hydraulic Institute (DHI).
BERM MIGRATION UNDER SCALED STORM EVENTS
Authors: Chapman Emily , Gangadharan Manoj K. , Idowu Temitope , Puleo Jack A.
Published: September 2023

Berms are one of the natural barriers protecting beaches from wave action and are the first intermittently exposed coastal feature to experience hydrodynamic forcing. Berms erode when storm activity mobilizes sediment offshore or carries it onshore through overwash. However, berm response under varied storm conditions requires further study. Pore water pressure response has been shown to potentially impact beach erosion (Stark, 2022). The infiltration from wave runup followed by exfiltration from rundown destabilize the sediment bed resulting in particle motion. Wave runup increases bed shear stress (Sumer, 2011), and horizontal pressure gradients have been shown to mobilize sediment in the surf zone (e.g. Anderson, 2017). Erosion occurs from numerous physical processes acting together to mobilize the sediment. This study aims to identify these physical processes and berm response for variety of scaled storm sequences.
MOORED SHIP MOTION FORECAST TOOL FOR THE PORT OF NGQURA
Authors: Troch Chris , Terblanche Luther , Rossouw Marius
Published: September 2023

Significant future growth is planned for the Port of Ngqura, but the Port does, however, suffer problems with moored container vessels. Under certain environmental conditions, these moored vessels experienced large motions, which lead to reduced operability or downtime and sometimes mooring line failures. One of the main contributing factors to the mooring problems is infra-gravity or long-waves (i.e. wave periods between approximately 25 s and 300 s), which induce basin and moored vessel resonance. A long-wave forecast system has been developed to assist the Port. Although this forecast system is accurate in predicting long-wave heights inside the Port, it does not give the port operators a full picture of the effects on moored vessels due to the complex nature of the interaction between these waves and the moored vessels. The long-wave forecasts alone are therefore difficult to interpret if the port operators do not have a background in vessel dynamics. A new tool, in the form of a moored vessel motion prediction system, was therefore developed.
AN EXPERIMENTAL STUDY ON A COMPLIANT FLOATING PLATFORM WITH A FRONT BARRIER UNDER WAVE ACTION
Authors: Bi Cheng , Law Adrian Wing-Keung
Published: September 2023

In recent years, solar power production has become the major source of renewable energy to combat climate change (Sahu et al., 2016), and floating solar farms (FSFs) are being explored on water space such as reservoirs and lakes at various major cities (Bi et al., 2021). Compared to the traditional ground-based solar farm, FSF requires no land use and the power generation efficiency can be increased potentially due to the watercooling effect (Golroodbari and van Sark, 2020). In addition, the coastal environment with more water space is also being considered for future development of FSF. With coastal floating solar farms, the PV panels can be supported on top of a compliant platform consisting of interconnected floating modules (Dai et al. 2020). However, excessive displacement of the platform can be induced by the incident wave action which can affect its structural stability (Sree et al., 2022). In this study, we examine the use of a submerged tensioned barrier installed in front of the FSF at a finite distance to stabilize the floating platform. Experiments were conducted to investigate the effectiveness of this protection measure. The effects of barrier length, platform length, and spacing between the barrier and platform on the displacement of the platform are investigated with respect to the wave transmission and reflection. In the following, we shall briefly describe the experimental setup and show some of the results obtained.
LARGE SCALE LABORATORY OBSERVATIONS OF WAVE FORCE REDUCTION ON COASTAL BUILDINGS BY AN IDEALIZED MANGROVE FOREST
Authors: Lomonaco Pedro , Mitchell William , Kelty Kiernan , Cox Daniel , Tomiczek Tori
Published: September 2023

As coastal communities face increasing chronic and acute hazards, nature-based coastal engineering solutions have experienced a rapid growth in popularity and interest. Recent works on this topic have shown that this “green infrastructure” may be effective at mitigating coastal hazards and thus have potential as sustainable adaptation alternatives to traditional engineering solutions such as seawalls and breakwaters. However, the amount of protection that green infrastructure can provide has yet to be quantified broadly. The purpose of this study is to quantify the wave force attenuation on coastal buildings by an idealized mangrove forest at a prototype scale and provide guidance to engineers in the design and management of mangrove forests to reduce damage due to storm waves over moderate cross-shore distances.
FUTURE CHANGES IN EXTREME WAVES AND THEIR SEASONALITY IN THE MEDITERRANEAN SEA
Authors: Loarca Andrea Lira , Mentaschi Lorenzo , Besio Giovanni
Published: September 2023

Climate change impacts threaten coastal areas all over the world, driven by increasing extreme sea levels. With higher sea surface and air temperatures, continued sealevel rise and high exposure and vulnerability of about 20 million people living in low-lying coastal areas, climate change affects the Mediterranean Sea significantly more than the world average and is therefore defined as a vulnerability hotspot (Ali, 2022). Projected changes in waves vary on a regional and local scale and play a crucial role in future extreme coastal water levels and coastal impacts. Several past studies used Global Climate Models (GCM) with coarse spatial resolution to study the future changes of wave climate. However, wave models driven by high-resolution dynamicallydownscaled surface winds from Regional Climate Models RCM) allow an enhanced characterization of wave climate at local scale, which is fundamental for coastal impact assessment and adaptation studies. Here we present the analysis of extreme wave events and their seasonality using a state-of-the-art regional ensemble of wave climate projections developed with the numerical wave model Wavewatch III forced by surface wind field data of 17 EURO CORDEX GCM-RCMs.
INFRAGRAVITY WAVES AT A TIDAL INLET
Authors: Reniers Ad , Wit Floris de , Tissier Marion , Rijnsdorp Dirk
Published: September 2023

The generation and propagation of infragravity waves at sandy coasts has received significant attention (e.g. Herbers et al., 1994). This is in contrast with tidal inlets where both observations and modeling studies are scarce. Here we present novel observations and modeling of infragravity waves over an ebb-tidal delta located at Ameland, the Netherlands. The objective is to understand the evolution of the free and bound infragravity waves as they propagate from the deeper shelf onto an ebb-tidal shoal and into the ebbchannel, establish their pathways and examine the potential in sediment transport. The latter is important in view of the anticipated large-scale ebb-tidal delta nourishment at this location to protect the coast from future storm impacts.
GLOBAL WAVE CLIMATE TRENDS: WHAT DO THE SOUTHERN HEMISPHERE WAVE BUOYS TELL US?
Authors: Flocard Francois , Harley Mitchell , Carley James , Cox Ron
Published: September 2023

Australia’s national wave data network presently consists of around 35 directional wave buoys distributed across the Australian coastline, with 11 of these buoys have been in operation since the mid-seventies. South Africa is home to 4 offshore wave buoys which have operating since the early eighties. New Zealand wave buoy network is relatively younger, with 3 wave buoys in operation since the early 2000s. All of these buoys have been providing invaluable longterm historical wave data which have allowed the offshore and coastal scientific community to better assess extreme wave climates and their impact on the coastline. Additionally, these data records of wave observations are key for model validation and to better understand the effects of climate change on the local and regional wave climate.
A METHOD TO DETERMINE WAVE DESIGN CRITERIA WITH HIGHER ACCURACY
Authors: Soares Julia L. , Rosman Paulo C.C.
Published: September 2023

The biggest concern on coastal constructions is lower the risk of failure against environmental pressures, like waves. The effect of waves on the structures is considered in the equations raising the power of significant height (Hs) of 2 to 4. However, designing a project considering a wave height that is too conservative can significantly increase its cost and make it economically unfeasible. On the other hand, underestimating the wave height can result in a project's catastrophic failure or significant maintenance costs. This study proposes a new method to assess the wave heights for design criteria more accurately.
WAVE TRANSFORMATION AND RUNUP VARIABILITY DUE TO WAVE PHASE UNCERTAINTY
Authors: Bak A. Spicer , Lynett Patrick , Malej Matt , Salgado Gabriela , Hesser Tyler , Brodie Katherine
Published: September 2023

Wave runup is a significant portion of total water levels, particularly during storms (Sallenger, 2000). This makes accurate prediction of wave runup paramount. Wave runup can be estimated using simplified empirical models (e.g. Stockdon et al 2006) or simulated using phase-resolved Bousinesq models (Shi et al 2007, Lynett et al 2002) or non-hydrostatic models (e.g. Zijlema et al 2011). These models typically have a variety of offshore boundary input options ranging from spectral to time series, with the most broadly used being spectral parameterizations (e.g. JONSWAP, TMA, etc.) or direct spectral input, both of which neglect phase information at the offshore boundary. Recent research has highlighted the importance of the offshore boundary condition and wave phase at modeling wave runup (e.g. Fiedler et al 2019, Rutten 2021). This work pays careful attention to the consequences of the bound infragravity (IG) wave and explores the influence that unknown phase information can have on predicted wave transformation and resultant wave runup in the context of field observations.
CHANNEL CONCENTRATION AND ITS IMPACT ON NEARSHORE WAVE CONDITIONS
Authors: Modra Ben
Published: September 2023

Channel concentration is an important wave process in coastal regions. It occurs when a shallow water wave approaches a deep channel at a shallow angle, producing a localized region of increased wave height at the edge of the channel, and the early onset of wave breaking. Channel concentration can occur at dredge channels, so is of particular significance to port entrances and surrounding infrastructure, especially for breakwater heads. It also occurs at natural features such as submarine canyons, particularly where the canyon is perpendicular to the coastline. In contrast to refraction or channel reflection, channel concentration is not well documented in the available literature. While studies show wave concentration as a significant coastal process, there is insufficient information on the process to provide general design guidance for its consideration in harbour projects. As such, there is still the need to use design tools such as physical modelling to ensure the site specific wave conditions are characterised correctly.
THE JANUARY 2022 TONGA-HUNGA HA’APAI TSUNAMI WAVES ON THE EAST COAST OF AUSTRALIA, AND COMPARISON TO PREVIOUS EVENTS
Authors: Maddox Sam , Davies Gareth
Published: September 2023

On 15 January 2022 the Hunga Tonga-Hunga Ha’apai underwater volcano erupted. The eruption (ML5.8) generated pressure and surface waves that travelled across the globe. Figure 1 is the satellite imagery at the time of the eruption showing the scale of the blast. The eruption generated an atmospheric pressure wave that wrapped around the earth multiple times and was detected globally at atmospheric pressure gauges (Lynett, 2022). A tsunami was also generated at the volcano itself via some combination of the explosion and mass movements.
EXTREME WAVE CLIMATE OF THE NEW SOUTH WALES COAST
Authors: Garber Sean , Hanslow David , Taylor David , Dent Jarrod
Published: September 2023

The NSW coast is subject to a relatively moderate wave climate that is periodically affected by large coastal storm events arising from a range of synoptic weather systems. Extreme wave events may cause coastal inundation, beach erosion, damage to property and marine structures, and risks to public safety. This paper describes the statistical analysis of the extreme directional wave climate along the NSW coast based on historical wave buoy data extending back to 1974. From the analysis, long-term trends in the extreme wave climate (storm peaks, storm duration and peak directions) are also identified. The work is largely an extension of the analysis completed by Shand et al (2011), that incorporates an additional 13 years of wave data up to 2022.
DAMPING OF FINITE AMPLITUDE SOLITARY WAVES IN A FLUME
Authors: Wang Yufei , Liu Philip Li-Fan
Published: September 2023

Solitary wave is a permanent wave when the dissipation is ignored. Many analytical solutions have been developed for finite amplitude solitary waves. In additional to the perturbation solutions, closed form solutions are also available (e.g., McCowan 1891, Clamond and Fructus 2003, being denoted as CF from hereon), which are more accuracy, especially for larger amplitude solitary waves which were discussed in Wang and Liu (2022). In Wang and Liu (2022) ’s laboratory experiments, solitary waves are slowly damped along the wave flume, which can be attributed to the energy dissipation inside the boundary layers on the bottom and sidewalls. Keulegan (1948) first derived an approximate solution to describe the wave damping in the wave flume for small amplitude solitary wave. The basic idea of calculating the damping effect is that the rate of energy dissipation inside the boundary layers must be the same as the rate of wave energy loss. In this work, the same principle of energy balance is adopted for calculating the wave damping for finite amplitude solitary waves in a wave flume. The closed form solutions provided in CF are employed here for analyses.
CHARACTERISTICS OF BORES GENERATED BY DIFFERENT MECHANISIMS IN THE LABORATORY
Authors: Barranco Ignacio , Liu Philip L-F. , Chandler Ian
Published: September 2023

The present work focuses on investigating characteristics of tsunami-like bores generated by different generation systems in the laboratory. These characteristics include the bore strength, bore height and bore length. In this presentation we shall compare the bores generated employing the different generation mechanisms and provide analytical relations to aid in laboratory experimental design aiming to generate bores or inundations of specific characteristics. We shall also present an extended dataset of non-uniform bores generated employing the combination of dam-break, wavemaker and PLWG systems, including inundation and run-up measurements. In addition, the generation of N-bores is explored.
Sobre os mecanismos de superexploração da força de trabalho no Brasil no século XXI (2003-2019)
Authors: Aruto Pietro Caldeirini
Published: September 2023

A superexploração da força de trabalho constitui uma das categorias centrais da teoria marxista da dependência. O objetivo desse artigo é entender o sentido e os mecanismos da superexploração no Brasil nas duas primeiras décadas do século XXI. Os resultados apontam que na primeira década, durante o auge econômico cíclico, foi possível uma contenção relativa da superexploração, sobretudo no salário direto. Com a reversão do cenário externo e queda da taxa de lucro no início da segunda década a maior exploração do trabalhador, por meio de um maior desgaste físico e psíquico, parece recobrar sua centralidade na economia dependente.
As contribuições do Movimiento Evita para os bachilleratos populares argentinos
Authors: Ri Neusa Maria Dal , Gomes Mike Ceriani de Oliveira
Published: September 2023

O objetivo deste artigo é analisar as principais contribuições educacionais do movimento social argentino denominado Movimiento Evita (ME) para as escolas argentinas de jovens e adultos denominadas Bachilleratos Populares (BPs). O desenvolvimento da investigação se deu por meio das pesquisas bibliográfica, documental e empírica. Constatou-se que os BPs se encontram em um aperfeiçoamento constante de seus mecanismos democráticos internos para garantir a formação de seus estudantes, buscando superar a restrita demanda por títulos expedidos pelas escolas e o ME traz contribuições essenciais para o desvelamento do caráter político da educação, proporcionando uma formação científica e política para os estudantes dos BPs.
Study on the dynamic trends of moves into, out of, and within the city
Authors: Shimizu Yoko , Nakayama Toru , Shimizu Hiroko , Morita Hiroko
Published: September 2023

The purpose of this study was to compare the trends of moving in and out of the city and moving within the city, and to identify more detailed demographic and social dynamics within the city. The study found that the trends of moving in and out of the city and moving within the city can be classified into six categories and that moving within the city plays a significant role in the social dynamics of the region. Even though there was an increase in terms of population, some trends in moves in showed an aging of the population and its impact on the local community. In the case of a decrease in population due to partial moves out by households, the former households remain in the area, so it was found that moving out does not necessarily mean a decrease in the number of households, and this does not lead to the occurrence of vacant houses. From these findings, it can be said that the trend of moving within the city should be taken into account when considering the future image of the community. We think that it is necessary to understand the events occurring in the region in more detail and reflect them in future land use and housing policy considerations in the planning process.
Silver Ions Assisted Inversion Temperature Crystallization of 2D Cs3Bi2Br9 Nanoflakes for Highly Sensitive X‐Ray Detection
Authors: Zheng Zhi , Li Haiyang , Hai Liang , Ma Ruiqi , Liu Rui , Zhai Chunpeng , Sun Zongdong , Wang Fei , Ma Ying , Xie Qingguo , Lou Xiaoding , Zhai Tianyou , Xia Fan
Published: September 2023

2D perovskites have attracted wide attention for optoelectronic applications because of their unique layer structure and tunable outstanding optical/electrical properties. In addition, 2D Cs3Bi2Br9 nanoflakes possess large effective atomic number, high resistivity, high density as well as excellent stability, rendering it a promising material for X‐ray detection. Nevertheless, it is full of challenges to synthesize 2D Cs3Bi2Br9 nanoflakes by conventional inversion temperature crystallization (ITC) strategy due to the existence of Br‐ vacancies in the Cs3Bi2Br9 crystal nucleus. Herein, an Ag+ assisted ITC (SAITC) strategy to grow 2D Cs3Bi2Br9 nanoflakes is proposed. The synthesis mechanism revealed by both experiments and theoretical calculations can be mainly ascribed to the passivated Br− vacancies and enhanced structure stability by adding Ag+ which can effectively prevent the oxidation of 2D Cs3Bi2Br9 nanoflakes from growth of hybrid crystals. The synthesized high‐crystallinity 2D Cs3Bi2Br9 nanoflakes possess direct bandgap characteristic, and the mobility lifetime can reach 9.8 × 10−4 cm2 V−1. Excitingly, the fabricated device based on 2D Cs3Bi2Br9 nanoflakes demonstrates ultrahigh sensitivity of detecting X‐ray (1.9 CGyair−1cm−2) at very low driven voltage (0.5 V) due to the photoconductive gain mechanism. The 2D Cs3Bi2Br9 nanoflakes synthesized by SAITC method have great potential for developing highly sensitive optoelectronic devices.
Biosourced Antioxidants for Chemical Durability Enhancement of Perfluorosulfonic Acid Membrane
Authors: Agarwal Tanya , Adhikari Santosh , Babu Siddharth Komini , Prasad Ajay K. , Advani Suresh G. , Borup Rodney L.
Published: September 2023

The chemical durability of perfluorosulfonic acid (PFSA) membranes is a topic of growing interest to meet Department of Energy (DOE) durability targets for heavy‐duty vehicle (HDV) applications. State‐of‐the‐art membranes like Nafion, rely on the use of cerium, heteropolyacids, and other inorganic additives to increase PFSA chemical durability. A less explored avenue for the oxidative stabilization of PFSA and hydrocarbon membranes is the use of organic antioxidants. No reversible organic antioxidant has been demonstrated to date which can enhance membrane lifetime by factors comparable to cerium. Here, ellagic acid (EA) is demonstrated as a promising radical scavenger for PFSA's. It is found that the incorporation of EA enhances the chemical durability of Nafion by 160%. EA, when incorporated with cerium as an electron donorenhances Nafion durability by at least 80% compared to a membrane incorporated with just cerium in DOE‐defined durability tests. EA is found to be reversible in acidic conditions like those of fuel cells and its reversibility could be further enhanced by the use of suitable co‐antioxidants.
Simple and Low‐Cost Vanadyl Oxalate as Hole Transporting Layer Enables Efficient Organic Solar Cells
Authors: Li Mengdi , Zhang Yuefeng , Xia Dongdong , Fang Jie , Xie Qian , Li Yanxun , Zhao Chaowei , Xiao Chengyi , You Shengyong , Zhang Jicai , Jiang Lang , Jen Alex K.‐Y. , Li Weiwei
Published: September 2023

Organic solar cells (OSCs) with the conventional configuration usually use polyethylenedioxythiophene:polystyrene sulfonate (PEDOT:PSS) as the hole‐transporting layer (HTL); however, its acidity tends to affect the performance and long‐term stability of the devices. Therefore, replacing PEDOT:PSS with other more stable HTLs is essential for realizing the practical applications of OSCs. To achieve this goal, a simple and low‐cost vanadyl oxalate (VOC2O4) is identified as a HTL to facilitate high power conversion efficiencies (PCEs), good stability, and high thickness tolerance to be achieved in OSCs. The VOC2O4 thin film can be easily prepared by spin‐coating from its aqueous solution onto ITO/glass substrate and thermally annealed at 100 °C to exhibit high transmittance, conductivity, and work function. It can be applied as a robust HTL with wide processing conditions, especially after being heated at 200 °C and treated with UV‐ozone (UVO) to afford a very high PCE of 18.94% in OSCs. This value is among the highest PCEs obtained for binary OSCs. In addition, the derived OSCs exhibit high thickness tolerance and better stability than those based on PEDOT:PSS as HTL. These results reveal that VOC2O4 is an excellent HTL for OSCs, having great potential for large‐area device applications.
Delayed Crystallization Kinetics Allowing High‐Efficiency All‐Polymer Photovoltaics with Superior Upscaled Manufacturing
Authors: Chen Tianyi , Zheng Xiangjun , Wang Di , Zhu Yuxuan , Ouyang Yanni , Xue Jingwei , Wang Mengting , Wang Shanlu , Ma Wei , Zhang Chunfeng , Ma Zaifei , Li Shuixing , Zuo Lijian , Chen Hongzheng
Published: September 2023

Though encouraging performance is achieved in small‐area organic photovoltaics (OPVs), reducing efficiency loss when evoluted to large‐area modules is an important but unsolved issue. Considering that polymer materials show benefits in film‐forming processability and mechanical robustness, a high‐efficiency all‐polymer OPV module is demonstrated in this work. First, a ternary blend consisting of two polymer donors, PM6 and PBQx‐TCl, and one polymer acceptor, PY‐IT, is developed, with which triplet state recombination is suppressed for a reduced energy loss, thus allowing a higher voltage; and donor–acceptor miscibility is compromised for enhanced charge transport, thus resulting in improved photocurrent and fill factor; all these contribute to a champion efficiency of 19% for all‐polymer OPVs. Second, the delayed crystallization kinetics from solution to film solidification is achieved that gives a longer operation time window for optimized blend morphology in large‐area module, thus relieving the loss of fill factor and allowing a record efficiency of 16.26% on an upscaled module with an area of 19.3 cm2. Besides, this all‐polymer system also shows excellent mechanical stability. This work demonstrates that all‐polymer ternary systems are capable of solving the upscaled manufacturing issue, thereby enabling high‐efficiency OPV modules.
Semi‐Transparent, Pixel‐Free Upconversion Goggles with Dual Audio‐Visual Communication
Authors: Shih Chun‐Jen , Lin Chao‐Yang , Chen Kai , Amin Nurul Ridho Al , Luo Dian , Hsu I‐Sheng , Akbar Abdul Khalik , Biring Sajal , Lu Chih‐Hsuan , Chen Bo‐Han , Yang Shang‐Da , Lee Jiun‐Haw , Liu Shun‐Wei
Published: September 2023

The intractable brittleness and opacity of the crystalline semiconductor restrict the prospect of developing low‐cost imaging systems. Here, infrared visualization technologies are established with large‐area, semi‐transparent organic upconversion devices that bring high‐resolution invisible images into sight without photolithography. To exploit all photoinduced charge carriers, a monolithic device structure is proposed built on the infrared‐selective, single‐component charge generation layer of chloroaluminum phthalocyanine (ClAlPc) coupled to two visible light‐emitting layers manipulated with unipolar charges. Transient pump‐probe spectroscopy reveals that the ClAlPc‐based device exhibits an efficient charge dissociation process under forward bias. This process is indicated by the prompt and strong features of electroabsorption screening. Furthermore, by imposing the electric field, the ultrafast excited state dynamic suggests a prolonged charge carrier lifetime from the ClAlPc, which facilitates the charge utilization for upconversion luminance. For the first time, >30% of the infrared photons are utilized without photomultiplication strategies owing to the trivial spectrum overlap between ClAlPc and the emitter. In addition, the device can broadcast the acoustic signal by synchronizing the device frequency with the light source, which enables to operate it in dual audio‐visual mode. The work demonstrates the potential of upconversion devices for affordable infrared imaging in wearable electronics.
Large–Area Graphene Electrode for Ferroelectric Control of Pb(Mg1/3Nb2/3)O3–PbTiO3 Single Crystal
Authors: Lee Gwanmu , Jung Moonyoung , Yun Yoojoo , Kang Hojin , Park Nahee , Kang Haeyong , Suh Dongseok
Published: September 2023

Large‐area monolayer graphene is utilized as a metallic electrode for a ferroelectric single‐crystal [Pb(Mg1/3Nb2/3)O3]m–[PbTiO3]n (PMNPT). Unlike conventional metal, whose properties remain unaffected by field‐induced charge carriers, graphene's unique Dirac‐cone band structure causes its carrier density to vary in response to the polarization state of contacting dielectrics. PMNPT capacitors with graphene‐only and graphene/Cr/Au electrodes exhibit similar polarization versus electric‐field curves. However, polarization switching in PMNPT and corresponding charge‐state conversion in the graphene electrode are observed in the device configuration of a graphene‐ferroelectric field‐effect transistor. Systematic analysis of graphene's source‐drain current variation reveals that experimental results align well with a theoretical model considering the intrinsically doped state in graphene and ferroelectric surface charge state in PMNPT. Furthermore, interfacial charge trapping discussed in many previous reports is not observed. These findings suggest that large‐area monolayer graphene effectively serves as an electrode for ferroelectric single‐crystal materials, irrespective of its atomically thin structure and ambipolar metallic nature.