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61.
Rachel Tallon 《New Zealand geographer》2013,69(2):150-157
Terms such as ‘Third World/First World’, ‘Developing/Developed’ are still in common usage despite many commentators and educators signalling that they are inadequate. Using empirical evidence from research in New Zealand, this paper discusses how these dividing terms may be under stress among young people who seek new ways of learning about places and people. In conceptualising the South Pacific, terms like ‘developing world’ may be challenged by young people. Debating these terms at all levels of education is important and should not merely be left to tertiary levels. 相似文献
62.
Geographies of age: thinking relationally 总被引:1,自引:0,他引:1
In contrast to recent treatment of other social identities, geographers' work on age still focuses disproportionately on the social-chronological margins – the very young and (to a far lesser extent) the very old – and rarely connects them directly. We outline the benefits of creating relational geographies of age, in order to build out from the recent explosion of children's geographies, and discuss three helpful concepts: intergenerationality, intersectionality and lifecourse. We suggest that participation provides one epistemological vehicle for getting beyond geographies which are mainly adults'. 相似文献
63.
This paper explores the partnership between a community group and a geography department to assess the wind energy potential of the Blueskin Bay region in southern New Zealand. The partnership has provided opportunities for research and is of strategic importance. Year‐long wind observations and numerical modelling have revealed that the hills surrounding Blueskin Bay show potential for wind energy generation. Despite challenges for both parties, the university–community partnership has allowed a successful research platform to be established. 相似文献
64.
Jacob Garty Lior Weissman Tal Levin Rachel Garty-Spitz Haya Lehr 《Journal of Atmospheric Chemistry》2004,49(1-3):251-266
To assess the impact of UV-B radiation combined with NaHSO3 in solution under laboratory conditions, we compared the amounts of stress-ethylene produced by two lichen species of the same genus. Ramalina lacera, an epiphytic Mediterranean lichen, was found to be rather sensitive to UV-B combined with NaHSO3, relative to the epilithic desert lichen R. maciformis. The impact of high temperatures with FeCl2 in solution, measured by amounts of stress ethylene accentuated the adaptability of R. maciformis to desert conditions, whereas R. lacera appeared to be rather sensitive to extreme temperatures especially in the case of chemical contamination. The adaptability of R. maciformis to UV-B appears to be related to the photoprotective capabilities of lichen substances. 相似文献
65.
Almost all engineering evacuation models define the objective as minimizing the time required to clear the region or total
travel time, thus making an implicit assumption that who will or should evacuate is known. Conservatively evacuating everyone
who may be affected may be the best strategy for a given storm, but there is a growing recognition that in some places that
strategy is no longer viable and in any case, may not be the best alternative by itself. Here, we introduce a new bi-level
optimization that reframes the decision more broadly. The upper level develops an evacuation plan that describes, as a hurricane
approaches, who should stay and who should leave and when, so as to minimize both risk and travel time. The lower level is
a dynamic user equilibrium (DUE) traffic assignment model. The model includes four novel features: (1) it refocuses the decision
on the objectives of minimizing both risk and travel time; (2) it allows direct comparison of more alternatives, including
for the first time, sheltering-in-place; (3) it uses a hurricane-scenario-based analysis that explicitly represents the critically
important uncertainty in hurricane track, intensity, and speed; and (4) it includes a new DUE algorithm that is efficient
enough for full-scale hurricane evacuation applications. The model can be used both to provide an evacuation plan and to evaluate
a plan’s performance in terms of risk and travel time, assuming the plan is implemented and a specified hurricane scenario
then actually occurs. We demonstrate the model with a full-scale case study for Eastern North Carolina. 相似文献
66.
Leah E. Morgan Madicken Munk Brett Davidheiser‐Kroll Nicholas H. Warner Sanjeev Gupta Rachel Slaybaugh Patrick Harkness Darren F. Mark 《Geostandards and Geoanalytical Research》2017,41(3):381-396
The chronology of the Solar System, particularly the timing of formation of extra‐terrestrial bodies and their features, is an outstanding problem in planetary science. Although various chronological methods for in situ geochronology have been proposed (e.g., Rb‐Sr, K‐Ar), and even applied (K‐Ar), the reliability, accuracy, and applicability of the 40Ar/39Ar method makes it by far the most desirable chronometer for dating extra‐terrestrial bodies. The method however relies on the neutron irradiation of samples, and thus a neutron source. Herein, we discuss the challenges and feasibility of deploying a passive neutron source to planetary surfaces for the in situ application of the 40Ar/39Ar chronometer. Requirements in generating and shielding neutrons, as well as analysing samples are described, along with an exploration of limitations such as mass, power and cost. Two potential solutions for the in situ extra‐terrestrial deployment of the 40Ar/39Ar method are presented. Although this represents a challenging task, developing the technology to apply the 40Ar/39Ar method on planetary surfaces would represent a major advance towards constraining the timescale of solar system formation and evolution. 相似文献
67.
Rumjana Mitzeva Boryana Tsenova Rachel Albrecht Walt Petersen 《Atmospheric Research》2009,91(2-4):299-309
Two different thunderstorms are simulated by two distinct one-dimensional cloud models using four different parameterisations of the non-inductive mechanism of electric charging, based on laboratory studies. The results demonstrate that during the early (pre-lightning) stage of thunderstorm electrification, simulated charge density depends not only on the model charging parameterisation employed, but also on the specific representations of the kinematics and microphysical characteristics of the model itself. Though no conclusions are drawn regarding the physical suitability of the charging parameterisations themselves, the analysis indicates that the most significant differences between the simulated charge structures of the clouds produced in each particular model are the result of different distributions of model cloud characteristics and of the type of parameterisation of the microphysical processes. The study reveals that it is too early to make any conclusion regarding which, if any, of the existing parameterisation schemes are better suited to the realistic simulation of electrical charging in real clouds. 相似文献
68.
Timothy Pietsch Justine Kemp Colin Pardoe Rainer Grün Jon Olley Rachel Wood 《第四纪科学杂志》2019,34(8):662-673
Kiacatoo Man, a large, rugged Aboriginal adult buried in the Lachlan riverine plains of southeastern Australia, was discovered in 2011. Laser‐ablation uranium series analysis on bone yielded a minimum age for the burial of 27.4 ± 0.4 ka (2σ). Single‐grain, optically stimulated luminescence ages on quartz sediment in which the grave had been dug gave a weighted mean age of 26.4 ± 1.5 ka (1σ). Luminescence samples from the grave infill and from sediment beneath the grave exhibit overdispersed dose distributions consistent with bioturbation or other disturbance, which has obscured the burial signal. The overlap between the minimum (U‐series) and maximum (luminescence) ages places the burial between 27.0 and 29.4 ka (2σ). Luminescence ages obtained from the channel belt of between 28 ± 2 and 25 ± 3 ka indicate that fluvial sedimentation was occurring before the Last Glacial Maximum, which is consistent with the broader geomorphic setting. Together, these results are internally and regionally consistent, and indicate that Kiacatoo Man was one of the more ancient individuals so far identified in Australia. His remains are important to our understanding of patterns of biological variation and other processes that have shaped people in the Murray‐Darling Basin through time. Copyright © 2019 John Wiley & Sons, Ltd. 相似文献
69.
William J. Chaplin Yvonne Elsworh Rachel Howe George R. Isaak Clive P. McLeod Brek A. Miller H. B. Van Der Raay Sarah J. Wheeler Roger New 《Solar physics》1996,168(1):1-18
Since 1981 we have been operating the Birmingham Solar-Oscillations Network (BiSON), a global network of resonant-scattering spectrometers, observing the low-l solar p modes. Here we discuss historical developments, culminating in the establishment of a 6-station network in 1992 September, and the subsequent performance of that network. The data record of each station from 1992 to 1994 has been analysed in terms of weather and equipment breakdowns. Our early experience suggests that the best long-term coverage possible with a 6-station network is limited in practice to about 80%, which falls short of previous predictions. 相似文献
70.
The properties of carbonate rocks are often the result of multiple, diagenetic events that involve phases of cementation (porosity occlusion) and dissolution (porosity enhancement). This study tests the hypothesis that the order of these events is a major control on final porosity and permeability. A three-dimensional synthetic model of grainstone is used to quantify trends that show the effect of early cementation, non-fabric selective dissolution, and then a second-generation of (post-dissolution) cement. Models are 3 mm3 with a resolution of 10 μm. Six simple paragenetic sequences are modelled from an identical starting sediment (without accounting for compaction) where the same diagenetic events are placed in different sequences, allowing for quantification of relative changes in the resultant porosity and permeability for each diagenetic event, the trajectory through time, as well as for each final rock. All modelled paragenetic sequences result in reductions in porosity and permeability, but the order of diagenetic events controls the trajectory and final rock properties. Differences in the order of early cement precipitation alone produce variable final values, but all follow the porosity–permeability relationship as expressed by the Kozeny-Carman equation. However, final values for the sequences which include a phase of dissolution fall on a new curve, which departs from that predicted by the Kozeny-Carman relationship. This allows an alternative form of porosity–permeability relationship to be proposed: κ = 2280ϕ–30,400, where ϕ is porosity (%) and κ is permeability (mD). Hence while the Kozeny-Carman relationship predicts porosity–permeability changes that occur with cementation, it is unable to capture accurately changes within the pore network as a result of dissolution. Although the results may be dependent on the properties of the initial carbonate sediment and simplified diagenetic scenarios, it is suggested that this new porosity–permeability relationship may capture some generalized behaviour, which can be tested by modelling further sediment types and diagenetic scenarios. 相似文献