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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]

This paper reports on the development of metalearning capacity in the learning of athreshold 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. [ABSTRACT FROM PUBLISHER]

Threshold concepts are transformative, integrative, and provocative; understanding these difficult concepts allows students to be capable of solving advanced problems. This investigation and evaluation of a metacognitive curricular approach explore variation in students' and teachers' discernment of structural complexity of concepts and its potential for enhancing students' learning and conceptual understanding of threshold concepts. Three trials of a metacognitive assessment activity administered to two cohorts of a civil engineering course (n = 276 andn = 264) were investigated. Students were presented with several answers (varying in structural complexity) to a question about a threshold concept and asked to mark each response. Quantitative analyses compared students' and teachers' marking schemes within and across trials, and qualitative analyses explored students' written reflections following the activity. Students' justifications for their marking schemes, their reflections on the activity's usefulness, and the convergence of students' and teachers' marking schemes suggest that the activity supported deep forms of student learning. [ABSTRACT FROM PUBLISHER]

A similarity parameter is derived to describe surf zone dissipation using the classical energy dissipation model for surf zone bores. This parameter can also be interpreted as a relative beach slope parameter, βγ, and, for shallow water sinusoidal waves, is the ratio of the local beach slope and the local wave steepness (H/L). βγ = 1 defines the boundary between two different energy dissipation regimes. Conditions with βγ<1 represent over-dissipative conditions, where the classical bore dissipation model provides more dissipation than that required for depth-limited waves (constant H/h) to be maintained. Conditions with βγ>1 represent under-dissipative conditions, where the bore model provides insufficient dissipation for depth-limited conditions to occur. Conditions with βγ = 1 at the breakpoint lead to locally saturated but not depth-limited surf. Hence, the new similarity parameter distinguishes between saturated and unsaturated surf conditions. Based on this bore dissipation model, an analytical model for the wave height transformation of monochromatic waves on planar beaches is derived. The cross-shore variation in wave height obtained from this model show different functional forms; concave upward for over-dissipative conditions and convex upward for under-dissipative conditions. Further, the analytical model shows that depth-limited conditions within the inner surf zone are not possible with this bore dissipation model and the model assumptions. Additional work is required to determine if this parameter is a useful predictor of other surf zone characteristics. Highlights: We derive a similarity parameter to describe surf zone dissipation. The similarity parameter defines the boundary of two dissipation regimes. The parameter distinguishes between saturated and unsaturated surf conditions. The classical bore dissipation model cannot predict depth-limited wave heights on a plane beach. [ABSTRACT FROM AUTHOR]