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201.
Anna Stevenson Jamie Pearce Tony Blakely Vivienne Ivory Karen Witten 《New Zealand geographer》2009,65(3):211-221
Over the past two decades, there has been a resurgence of interest into place‐based influences on health. Researchers have identified that various characteristics of neighbourhoods exert an influence on the health outcomes and behaviours of local residents. Understanding the processes linking places to health provides considerable potential for a range of policy interventions. We review the New Zealand‐based neighbourhoods and health research. Consideration is given to the types of neighbourhood characteristics, as well the range of health outcomes that have been studied. Finally, we suggest some priorities for further research into the mechanisms underpinning neighbourhood influences on health in New Zealand. 相似文献
202.
Luiza Dihoru Olafur Oddbjornsson Ben Cannell Adam J. Crewe Tony Horseman Matt Dietz Colin A. Taylor 《地震工程与结构动力学》2020,49(13):1308-1328
The advanced gas-cooled reactors (AGRs) are the backbone of the United Kingdom's nuclear generation fleet, producing approximately 17% of the country's electricity. Their safety cases are supported by thorough inspection and monitoring of their graphite cores and extensive theoretical, analytical, and experimental studies. This paper presents a unique, highly innovative and technically challenging earthquake engineering project that has provided vital evidence to underpin the seismic safety assessments of the AGRs. Two modelling approaches, one experimental (a multilayer array physical model), and one numerical (a SOLFEC nonsmooth contact dynamics computational model) have been developed to investigate the seismic behaviour of an aged graphite core. The synergetic relationship between the two approaches is a product of insightful collaborative learning between the University of Bristol and Atkins, with the experiments providing material parameters and validation data and the computer simulations feeding array design and test schedule recommendations to the physical model. The predictive capabilities of the physical and the numerical models are tested by direct comparison and the good agreement between the results has increased the confidence in both. The model's versatility allows a variety of core scenarios to be tested that can explore in detail the AGR core behaviour in seismic conditions. 相似文献
203.
Andrea Román-Sánchez Ana Laguna Tony Reimann Juan Vicente Giráldez Adolfo Peña Tom Vanwalleghem 《地球表面变化过程与地形》2019,44(10):2066-2080
Particles on soil-mantled hillslopes are subject to downslope transport by erosion processes and vertical mixing by bioturbation. Both are key processes for understanding landscape evolution and soil formation, and affect the functioning of the critical zone. We show here how the depth–age information, derived from feldspar-based single grain post-infrared infrared stimulated luminescence (pIRIR), can be used to simultaneously quantify erosion and bioturbation processes along a hillslope. In this study, we propose, for the first time, an analytical solution for the diffusion–advection equation to calculate the diffusivity constant and erosion–deposition rates. We have fitted this model to age–depth data derived from 15 soil samples from four soil profiles along a catena located under natural grassland in the Santa Clotilde Critical Zone Observatory, in the south of Spain. A global sensitivity analysis was used to assess the relative importance of each model parameter in the output. Finally, the posterior probability density functions were calculated to evaluate the uncertainty in the model parameter estimates. The results show that the diffusivity constant at the surface varies from 11.4 to 81.9 mm2 a-1 for the hilltop and hill-base profile, respectively, and between 7.4 and 64.8 mm2 a-1 at 50 cm depth. The uncertainty in the estimation of the erosion–deposition rates was found to be too high to make a reliable estimate, probably because erosion–deposition processes are much slower than bioturbation processes in this environment. This is confirmed by a global sensitivity analysis that shows how the most important parameters controlling the age–depth structure in this environment are the diffusivity constant and regolith depth. Finally, we have found a good agreement between the soil reworking rates proposed by earlier studies, considering only particle age and depth, and the estimated diffusivity constants. The soil reworking rates are effective rates, corrected for the proportion of particles actually participating in the process. © 2019 John Wiley & Sons, Ltd. 相似文献
204.
In the context of the current review of New Zealand's National Certificate of Educational Achievement (NCEA), the paper reflects on the nature and relevance of geography in education, life and work. The context of school geography programmes is critically examined, and a checklist of points for further consideration and action is presented. 相似文献
205.
Anita Latai-Niusulu Tony Binns Etienne Nel 《Singapore journal of tropical geography》2020,41(1):40-60
Being resilient in the face of climate change seems especially important for island societies, which face the effects of rising temperatures, unpredictable rainfall, changing wind patterns and sea level rise. To date, most studies of adaptation and resilience among Pacific island communities have used indicators and methods rooted in Western science and neo-classical economics. These have been criticized as being locally irrelevant and inadequate to appreciate the dynamic nature and social structures of island communities and their capacity to adapt. This paper challenges the paradigm that defines resilience as a return to equilibrium, by using a non-equilibrium, cultural ecological lens. The non-equilibrium view of resilience sees the social systems of island nations as highly dynamic and undergoing persistent adaptation in the face of changing environmental factors. Field-based research undertaken in eight villages in Samoa found that, through constant exposure to environmental change over extended periods of time, communities have become resilient and are in a position to adapt to future changes. In developing future policy in relation to climate change, Pacific island governments need to develop a more nuanced understanding of islanders’ perceptions and historical actions in the context of both their physical locations and their dynamic socio-cultural systems. 相似文献
206.
The ruby mines of Mogok 总被引:1,自引:0,他引:1
Tony Waltham 《Geology Today》1999,15(4):143-149
The world's finest rubies all come from the metamorphic rocks of Mogok, in Myanmar. Traditional methods of mining, with little mechanization, are still used; they work best in digging the gemstones out of narrow calcite veins and thin beds of buried placer gravel. 相似文献
207.
Jean-François Crétaux Stephane Calmant Vladimir Romanovski Anton Shabunin Florent Lyard Muriel Bergé-Nguyen Anny Cazenave Fabrice Hernandez Felix Perosanz 《Journal of Geodesy》2009,83(8):723-735
Altimetry missions such as Topex/Poseidon, Jason-1, GFO and ENVISAT have been widely used in the continental domain over lakes,
rivers and wetland although they were mostly dedicated to oceanic studies. Knowledge of the instrumental biases is a key issue.
Numerous sites have been dedicated to calibration purposes, either in the oceanic domain (Harvest offshore platform in California,
Corsica, Bass Strait in Australia) or over lakes (Lake Erie in United States). A new site (Lake Issykkul in Kirghizstan) is
proposed for calibration in the continental domain. This lake is covered by past (T/P) and current radar altimetry satellites
(Jason-1, T/P, GFO, and ENVISAT). Several in situ water levels and local meteorological variables are available at the site.
Located in a mountainous area, it offers an opportunity for calibration far away from all other existing sites and very different
environment contexts. Two GPS campaigns have been conducted on the lake in 2004 and in 2005. They consisted of cruises with
stations installed onboard a boat following the satellite ground tracks, and onshore settings. This enabled estimating a bias
for each altimeter and each tracking algorithm available. Biases obtained for Envisat, GFO, T/P and Jason-1 using the default
ocean tracker (respectively, 48.1 ± 6.6, 7.5 ± 4.0, 0 ± 4.3 and 7.0 ± 5.5 cm) agree with biases published at the other calibration
sites. For Jason-1, there is a significant disagreement with results obtained in the ocean field (7 cm instead of 13 cm) but
is coherent with bias obtained on the Lake Erie site. Erroneous estimates of the sea state bias correction from non-oceanic-like
waveforms is discussed as a possible explanation. Errors in the ionospheric, wet and dry tropospheric corrections for the
continental domain are also highlighted and quantified. 相似文献
208.
Tony O. Henninger P. William FronemanNicole B. Richoux Alan N. Hodgson 《Estuarine, Coastal and Shelf Science》2009
The role of submerged macrophytes as refugia from fish predation and as possible food sources for the estuarine isopod Exosphaeroma hylocoetes ( Barnard, K.H., 1940) was investigated. Laboratory experiments tested the effectiveness of artificial vegetation, replicating submerged vegetation, in enabling isopods to elude selected fish predators Rhabdosargus holubi, Glossogobius callidus, Monodactylus falciformis and Clinus cottoides. Isopods preferentially hid in the vegetation (>90%), even in absence of fish. The predatory fish had varying success in finding isopods within the vegetation. Isopod mortality ranged from 2% (R. holubi) to a maximum of 87% (C. cottoides) within vegetation, depending on the fish predator present. Stable isotope and fatty acid analyses ruled out the submerged macrophyte Ruppia maritima and inundated fringing grasses as direct food sources, but highlighted the epiphytic biota (mainly diatoms) found on the submerged vegetation and sediments as more likely food sources. These findings are consistent with gut content analyses. The results suggest that the close association of E. hylocoetes with R. maritima is the result of the vegetation providing the isopod with a refuge against fish predation as well as areas of increased food availability. 相似文献
209.
Ian L. Turner Paul E. Russell Tony Butt Chris E. Blenkinsopp Gerd Masselink 《Coastal Engineering》2009
This paper replies to TE Baldock's discussion [Coastal Eng. 56 (2009) 380–381] of ‘Measurement of wave-by-wave bed-levels in the swash zone’ by Turner et al. [Coastal Eng. 55 (2008) 1237–1242]. We address and extend the comparison and discussion of ultrasonic bed-level sensors and buried pressure transducers to obtain estimates of the beach face elevation within the swash zone. We demonstrate the use of the former method to obtain many and continuous (every time the beach face is exposed) in-situ estimates of net sediment flux per swash. 相似文献
210.
An evaluation of progress in implementing ecosystem-based management of fisheries in 33 countries 总被引:1,自引:0,他引:1
Tony J. Pitcher Daniela Kalikoski Katherine Short Divya Varkey Ganapathiraju Pramod 《Marine Policy》2009
The performance of 33 countries was evaluated for ecosystem-based management (EBM) of fisheries in three fields (principles, criteria and implementation) using quantitative ordination including uncertainty. No country rated overall as ‘good’, only four countries were ‘adequate’, while over half received ‘fail’ grades. A few developing countries performed better than many developed nations. Two case studies test the method. In Indonesia, Raja Ampat and Papua, rated similar to the national evaluation, but better performance might follow successful implementation of a planned EBM initiative. A workshop in Australia rated regional fisheries managed by New South Wales 20% lower for EBM than federally managed fisheries. 相似文献