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This paper reports on the development of metalearning capacity in the learning of a "threshold concept"--capacity of transformative significance relative to metalearning in the general response context of a discipline or subject. The development of metalearning capacity is framed within a protocol that invites students to self-construct a "learning profile" of themselves; reflect on it in light of theoretical considerations; and accordingly self-initiate changes to their learning behaviour. Findings are consistent with other studies in different disciplinary contexts that employed the same methodology--namely, that metalearning activity can be successfully focused on a particular threshold concept to benefit a substantial majority of students in a variety of ways ranging across a positive reinforcement of self, a change in conception of what "learning is," to self-initiated change. Metalearning activity is advocated as a theoretically sound, and pedagogically driven, learning intervention--one that adds value to the student learning experience.

This paper describes the pedagogical impact of real-world experimental projects undertaken as part of an advanced undergraduate fluid mechanics subject at an Australian university. The projects have been organized to complement traditional lectures and introduce students to the challenges of professional design, physical modelling, data collection and analysis. An overview of two projects is presented: wind tunnel testing of buildings and wave loading on piles. Both studies are undertaken as group work within the undergraduate subject. The pedagogy of the projects is discussed in terms of the classical educational psychology literature concerning project-based learning, collaborative and guided learning and reflection. In terms of learning outcomes, the primary aim is to enable students to deliver a professional report as the final product, where physical model data are compared to ideal-fluid flow calculations and real-fluid flow analyses. Thus the students are exposed to a professional design approach involving a high level of expertise in fluid mechanics, with sufficient academic guidance to achieve carefully defined learning goals, while retaining sufficient flexibility for students to construct their own learning goals. The overall pedagogy is a blend of problem-based and project-based learning, which reflects academic research and professional practice. The assessment is a mix of peer-assessed oral presentations and written reports that aims to maximize student reflection and development. Student feedback indicated a strong motivation for courses that include a well-designed project component. (Contains 1 table and 3 figures.)

Laboratory measurements of the interaction between high‐frequency (HF) wind‐waves and low frequency (LF) paddle waves are presented. The measurements were made in a wind‐wave flume with wind and paddle waves propagating in the same direction. The primary objective is to examine the physical mechanisms proposed to explain the suppression of wind‐waves due to presence of swell (here paddle waves). For this purpose, the precise time scale of the temporal transition from wind‐only to wind‐plus‐paddle conditions is examined. The results reveal that the majority of wind‐wave suppression occurs too quickly to have been caused by reduced wind‐input, instead indicating that enhanced HF wave dissipation is the primary suppression mechanism. The spatial variation in HF wave energy along the LF wave phase indicates that HF suppression mainly occurs on the LF wave crest, and high on the windward face, which are the locations that experience the highest wind velocities. This observation also suggests that the reduced wind‐input is not the primary suppression mechanism. Quantification of HF wave suppression versus a broad range of wind velocities, paddle wave conditions and fetch did not reveal any critical dependence of suppression on LF wave breaking or wind separation at LF wave crests. It is concluded that suppression occurs primarily due to enhanced dissipation of HF waves near LF wave crests. This mechanism is proposed to be coupled to the wind velocity, where an increased wind velocity near LF wave crests exceeds the level of forcing that HF waves of low C/u* can withstand without breaking. Plain Language Summary: Wind action on water surface results in generation and growth of wind‐waves. Observations have shown that the presence of swell traveling in the wind direction suppresses the wind‐waves. There is however no consensus on the physical mechanisms behind this effect. In this study, the proposed mechanisms are examined through laboratory observations of the interaction between wind‐waves and paddle waves. This includes observations of the precise transition time scale as paddle waves enter an existing wind‐wave field. The rapidity of suppression indicates that wind‐waves are actively erased by paddle waves, more so than being inhibited in their growth which is a slower process. The measurements also reveal that suppression of wind‐waves mainly occurs near the crest of paddle waves, and high on their windward face, which are the locations most exposed to the wind. Both observations indicate that enhanced dissipation of wind‐waves is the primary mechanism of their suppression, while the reduction of wind energy input to wind‐waves only plays a secondary role. The enhanced dissipation of wind‐waves is suggested to be linked to the wind velocity, with wind‐waves breaking at the crest of paddle waves as the excess wind velocity at this location exceeds the threshold the wind‐waves can withstand. Key Points: Enhanced energy dissipation is the primary mechanism behind wind‐wave suppression during interaction with swellSuppression of HF waves in the presence of LF waves mainly occurs on the LF wave crest, and high on its windward faceLF wave breaking and wind separation from LF waves are not essential for HF waves suppression during swell, but may play a secondary role [ABSTRACT FROM AUTHOR]

This study provides the first ever published measurements of scour and morphological change around an Oscillating Water Column (OWC) Wave Energy Converter (WEC) device at a real-world site, with the intention of informing future designs to reduce costs of the technology. A 200-kW prototype OWC WEC was deployed at King Island, Tasmania, Australia in January 2021, providing a unique opportunity to monitor the device using a combination of dive footage, multi-beam surveys and bedrock surveys. Settlement of the device was observed and monitored before ceasing once the foundation made contact with the underlying bedrock at the site. It is hypothesized that the settlement is caused by scour undermining the gravity structure's foundations. The processes causing this scour are explored and possible future design modifications are suggested to reduce the risk of scour and settlement. [ABSTRACT FROM AUTHOR]

Wave measurements from a new, low-cost, real-time wave buoy (Spotter) are investigated in a comparative study as part of a site characterization study at a wave energy candidate site at King Island, Tasmania, Australia. Measurements from the Sofar Ocean Spotter buoy are compared with concurrent measurements from a Teledyne RD Instrument (RDI) 1200 kHz Work Horse ADCP and two RBRsolo3 D wave16 pressure loggers. The comparison period between 8 August and 12 October 2019 provides both the shallowest and longest continuous published comparison undertaken with the Spotter buoy. Strong agreement was evident between the Spotter buoy and RDI ADCP of key wave parameters including the significant wave height, peak wave period, and mean wave direction, with the mean values of those parameters across the full deployment period agreeing within 3%. Surface wave spectra and directional spectra are also analyzed with good agreement observed over the majority of the frequency domain, although the Spotter buoy records approximately 17% less energy within a narrow frequency band near the peak frequency when compared to the RDI ADCP. Measurements derived from the pressure loggers routinely underestimated the significant wave height and overestimated the mean wave period over the deployment period. The comparison highlights the suitability of the Spotter buoy for low-cost wave resource studies, with accurate measurements of key parameters and spectra observed. [ABSTRACT FROM AUTHOR]

The use of physics-based wave propagation predictions requires a considerable time commitment, a high level of expertise and extensive climate and reef data that are not always available when undertaking planning for management of coasts and coral reef ecosystems. Bayesian belief networks (BBNs) have at least three attributes that make them an excellent choice to communicate physics-based wave model predictions. First, BBNs subsume thousands of predictions to provide probabilistic outcomes. Second, by using prior probabilities, a practitioner can still obtain predictions of wave outcomes even when their knowledge of input parameters is incomplete. Third, BBNs can propagate evidence from outputs to inputs, which can be used to identify input conditions that are most likely to deliver a chosen outcome. These three attributes are tested and found to hold for a BBN developed for this purpose. [ABSTRACT FROM AUTHOR]

Coastal engineers design harbors, coastal structures, and beach protection measures to guard infrastructure and communities located in coastal zones. The accurate forecasting of coastal erosion and inundation is crucial for planning the protection of existing and new coastal zone infrastructure. [ABSTRACT FROM PUBLISHER]

A one-dimensional lattice Boltzmann model is developed to solve the shallow water equations for steady and unsteady flows within both the subcritical and supercritical regimes. Previous work is extended through a generalized Galilean transformation applied to the standard scheme. The transformation yields a general asymmetric lattice Boltzmann model scheme which can successfully model a wide range of both subcritical and supercritical flow regimes, and enables implementation of the asymmetric model for practical purposes. In current work, a new set of equilibrium functions, boundary conditions and the external force weights are derived for the generalized transformed scheme. A new stability region is also defined, allowing selection of a lattice speed that maintains numerical stability for a wider range of sub- and supercritical flows and combinations of those flow conditions, compared to the previous scheme with fixed asymmetry. The model is validated against a range of benchmark cases in open-channel hydraulics that demonstrate the applicability of the new model. [ABSTRACT FROM PUBLISHER]

Power, H.E.; Nielsen, P.; Hughes, M.G.; Aagaard, T., and Baldock, T.E., 2016. Wave height distributions in the surf zone on natural beaches. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 917-921. Coconut Creek (Florida), ISSN 0749-0208. Wave height distributions in the surf zone are examined using a large existing field dataset. Observed distributions are compared to the Rayleigh distribution, the Weibull distribution, and the normal distribution. In more than half the 15-minute data runs (57%), wave height distributions were statistically significantly different to a Rayleigh distribution, of which the majority were more narrowly distributed, with fewer extrema. In contrast, only 6% of distributions were statistically significantly different to a normal distribution. The distributions were observed to become narrower with decreasing depth. Data were subsequently fitted to a Weibull distribution with a varying exponent to allow for a change in the shape of the distribution with changing depth. The data show distributions with a wide range of exponents, but a mean of 2.4 indicating that, on average, data are more narrowly distributed than a Rayleigh distribution (exponent of 2). The value of the exponent was observed to increase in shallower water, with a strong inverse correlation between depth and the exponent. [ABSTRACT FROM AUTHOR]