Research institution
University of Canterbury
NZ
6 researchers0 verified7 linked papers8,612 indexed citations
Researchers
Public research profiles associated with University of Canterbury.
Research from this institution
Publications linked through researcher authorship records.
1988 · Journal of Structural Engineering · 8,396 citations
Theoretical Stress‐Strain Model for Confined Concrete
A stress‐strain model is developed for concrete subjected to uniaxial compressive loading and confined by transverse reinforcement. The concrete section may contain any general type of confining steel: either spiral or circular hoops; or rectangular hoops with or without supplementary cross ties. These cross ties can have either equal or unequal confining stresses along each of the transverse axes. A single equation is used for the stress‐strain equation. The model allows for cyclic loading and includes the effect of strain rate. The influence of various types of confinement is taken into account by defining an effective lateral confining stress, which is dependent on the configuration of the transverse and longitudinal reinforcement. An energy balance approach is used to predict the longitudinal compressive strain in the concrete corresponding to first fracture of the transverse reinforcement by equating the strain energy capacity of the transverse reinforcement to the strain energy stored in the concrete as a result of the confinement.
2019 · 146 citations
Biology and Ecology of the Globally Significant Kelp Ecklonia radiata
Ecklonia radiata is one of the most widespread kelps globally, dominating temperate reefs throughout much of Australasia and southeastern Africa. Throughout much of its range, it is the only laminarian kelp and hence plays a key role in facilitating biodiversity and driving food webs, and it underpins immense ecological and socioeconomic values. This review synthesises the growing literature on E. radiata from its phylogeny and distribution through to its biology, ecology and recent changes. 266 It provides an assessment of the state of knowledge and identifies gaps in our understanding of this important species. Despite being tolerant of a wide range of abiotic conditions, recent environmental change has caused direct and indirect loss of E. radiata forests, with extensive areas transitioning to turf and urchin barrens. Ongoing climate change may require application of multifaceted and novel strategies to increase its resistance and resilience to future conditions. By integrating variation across space, time and environmental change, this review provides a description of the current status and possible future trajectories of E. radiata forests.
2019 · 50 citations
Oceanography and Marine Biology
Coastal plankton show fluctuations in abundance and species composition. Resting stage (cyst) production is a common strategy adopted by hundreds of plankton species to ensure reproduction and to avoid adverse conditions. During the resting period, these species are normally absent from the water column, and cysts produced in the plankton accumulate in the sediment where they wait for the return of suitable conditions. A portion of the cyst bank does not hatch, instead undergoing a dormancy that may extend for decades. Confined coastal areas accumulate cysts in sediment due to one or more possibilities, including reduced water movement/hydrodynamics, high population density, abundance of cyst-producing species, and the absence or scarcity of possible cyst consumers in the benthos. The pelagic-benthic nexus, which affects both the sediment and the water column (and possibly sea ice) is still poorly understood. In fact, the presence of cysts in the life cycle of organisms is likely to have considerable consequences for the ecology of coastal plankton, as well as the evolution and biogeography of species. This review aims to depict the presence (and even abundance) of resting stages in marine environments and their impact on ecosystem functioning. The review starts with a description of encysted resting stages in all marine planktonic taxa, listing a total of 501 species with known cysts, and methods and tools for their collection and study. The physiology and timing of the rest period is then described for various taxa, followed by a discussion of the evolutionary implications of resting. The presence of encysted stages in different realms and phyla of plankton suggests an ancient origin and a successive diversification of morphologies that, today, roughly characterise each taxa. Ecological and biogeographical implications stem from this general framework and support the hypothesis of seasonal occurrences of planktonic life in ecosystems where productivity is suspended for a long time (e.g. in polar seas). The potential to suspend or resume life has implications for human activities, such as the risk of translocations through ship ballast water and contamination of water and seafood with toxins but also the benefit of cysts for the production of aquaculture feed. The review concludes with perspectives on present knowledge and outstanding questions to address in future studies.
2016 · The Australian journal of teacher education · 12 citations
Physics Teachers’ Views on their Initial Teacher Education
This paper explores New Zealand (NZ) physics teachers’ and physics educators’ views about Initial Teacher Education (ITE). Perspectives of physics teachers nationally indicated that in general, teachers considered themselves not well-prepared in some content areas including electronics, modern physics, and atomic and nuclear physics. This may be because in NZ, physics teachers have usually gained their content knowledge from an undergraduate science degree where they may have only taken one or two courses in physics. One year postgraduate teacher education programmes do not have sufficient time to cover the physics content taught in the final three years of schooling. The implications for ITE of physics teachers are discussed in terms of the shifts needed to help them to identify the gaps in their content knowledge and to develop their conceptual understanding of physics.
2018 · InTech eBooks · 4 citations
Professional Development and Physics Teachers’ Ongoing Learning Needs
This study sought insight into the professional learning and development needs of physics teachers in New Zealand high schools. It used a mixed methods approach that comprised a national survey of high-school physics teachers as well as interviews with high-school physics teachers and physics teacher educators. Data from the teacher survey were analysed using descriptive statistical methods. Audio recordings from interviews were transcribed, analysed and used to triangulate and add depth to the survey data. Findings indicated that physics teachers were dissatisfied with the lack of formal physics-focussed professional development opportunities available to support their professional growth. Instead, teachers tended to rely on personal critical inquiry and infrequent practitioner meetings to inform practice. Suggestions for how to support the professional development needs of physics teachers better are discussed.
2016 · The Australian journal of teacher education · 4 citations
Physics Teachers’ Views on their Initial Teacher Education
This paper explores New Zealand (NZ) physics teachers’ and physics educators’ views about Initial Teacher Education (ITE). Perspectives of physics teachers nationally indicated that in general, teachers considered themselves not well-prepared in some content areas including electronics, modern physics, and atomic and nuclear physics. This may be because in NZ, physics teachers have usually gained their content knowledge from an undergraduate science degree where they may have only taken one or two courses in physics. One year postgraduate teacher education programmes do not have sufficient time to cover the physics content taught in the final three years of schooling. The implications for ITE of physics teachers are discussed in terms of the shifts needed to help them to identify the gaps in their content knowledge and to develop their conceptual understanding of physics.
2002 · AIP conference proceedings · 0 citations
Topic 1: Attracting Girls Into Physics
We discuss the problems in attracting girls into physics. We present some of the projects undertaken in various countries to ameliorate the problem, and we conclude with some follow‐up suggestions that can be implemented in all countries.