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921.
Crafting Regional Cultural Production: emergence,crisis and consolidation in the Gold Coast surfboard industry 总被引:1,自引:0,他引:1
Andrew Warren 《The Australian geographer》2013,44(4):365-381
Surfboard-making is concentrated in regions with vibrant surfing subcultures, suitable waves and sufficient expertise in crafting boards, by hand, to suit prevailing coastal conditions. This article charts the rise of the Gold Coast as Australia's most concentrated cluster of surfboard-making, from its origins as do-it-yourself craft in backyards and sheds, to professional, export-oriented industry. Out of highly informal, subcultural origins, a regional cluster emerged in the 1960s, fuelled by the growth of surfing, tourism and suburban development, and by the needs of surfers for customised boards that suit their body size, surfing style and local wave conditions. What transpired was a vernacular form of coastal creative industry combining craft skills, subcultural knowledge and design flair. Nevertheless, a mix of factors, including automation, increased competition from cheap imports, increasingly aggressive retail trade, and mistrust among board-makers, has threatened viability. Some workshops overextended into export production, marketing and automation, and consequently suffered from exposure to risk (as well as a commensurate decline in regional tourism). Others survived, and in some ways turned full circle: those small workshops continuing to service local markets, within their means, were most able to ride out the industry's turbulent times. Small-scale cultural production persists despite the volatility of the larger brands, geared instead around loyal customers who want hand-crafted boards made by shapers who they know and trust. 相似文献
922.
Philip T. Harte Joseph D. Ayotte Andrew Hoffman Kinga M. Révész Marcel Belaval Steven Lamb J. K. B?hlke 《Hydrogeology Journal》2012,20(6):1189-1201
Anthropogenic sources of carbon from landfill or waste leachate can promote reductive dissolution of in situ arsenic (As) and enhance the mobility of As in groundwater. Groundwater from residential-supply wells in a fractured crystalline-rock aquifer adjacent to a Superfund site in Raymond, New Hampshire, USA, showed evidence of locally enhanced As mobilization in relatively reducing (mixed oxic-anoxic to anoxic) conditions as determined by redox classification and other lines of evidence. Redox classification was determined from geochemical indicators based on threshold concentrations of dissolved oxygen (DO), nitrate (NO 3 – ), iron (Fe2+), manganese (Mn2+), and sulfate (SO 4 2– ). Redox conditions were evaluated also based on methane (CH4), excess nitrogen gas (N2) from denitrification, the oxidation state of dissolved As speciation (As(III) and As(V)), and several stable isotope ratios. Samples from the residential-supply wells primarily exhibit mixed redox conditions, as most have long open boreholes (typically 50–100?m) that receive water from multiple discrete fractures with contrasting groundwater chemistry and redox conditions. The methods employed in this study can be used at other sites to gauge redox conditions and the potential for As mobilization in complex fractured crystalline-rock aquifers where multiple lines of evidence are likely needed to understand As occurrence, mobility, and transport. 相似文献
923.
924.
Michael M. McGlue Aguinaldo Silva Hiran Zani Fabrício A. Corradini Mauro Parolin Erin J. Abel Andrew S. Cohen Mario L. Assine Geoffrey S. Ellis Mark A. Trees Sidney Kuerten Frederico dos Santos Gradella Giliane Gessica Rasbold 《Quaternary Research》2012,78(2):285-294
The Pantanal is the world's largest tropical wetland and a biodiversity hotspot, yet its response to Quaternary environmental change is unclear. To address this problem, sediment cores from shallow lakes connected to the Upper Paraguay River (PR) were analyzed and radiocarbon dated to track changes in sedimentary environments. Stratal relations, detrital particle size, multiple biogeochemical indicators, and sponge spicules suggest fluctuating lake-level lowstand conditions between ~ 11,000 and 5300 cal yr BP, punctuated by sporadic and in some cases erosive flood flows. A hiatus has been recorded from ~ 5300 to 2600 cal yr BP, spurred by confinement of the PR within its channel during an episode of profound regional drought. Sustained PR flooding caused a transgression after ~ 2600 cal yr BP, with lake-level highstand conditions appearing during the Little Ice Age. Holocene PR flood pulse dynamics are best explained by variability in effective precipitation, likely driven by insolation and tropical sea-surface temperature gradients. Our results provide novel support for hypotheses on: (1) stratigraphic discontinuity of floodplain sedimentary archives; (2) late Holocene methane flux from Southern Hemisphere wetlands; and (3) pre-colonial indigenous ceramics traditions in western Brazil. 相似文献
925.
Social media generated from many individuals is playing a greater role in our daily lives and provides a unique opportunity to gain valuable insight on information flow and social networking within a society. Through data collection and analysis of its content, it supports a greater mapping and understanding of the evolving human landscape. The information disseminated through such media represents a deviation from volunteered geography, in the sense that it is not geographic information per se. Nevertheless, the message often has geographic footprints, for example, in the form of locations from where the tweets originate, or references in their content to geographic entities. We argue that such data conveys ambient geospatial information, capturing for example, people’s references to locations that represent momentary social hotspots. In this paper we address a framework to harvest such ambient geospatial information, and resulting hybrid capabilities to analyze it to support situational awareness as it relates to human activities. We argue that this emergence of ambient geospatial analysis represents a second step in the evolution of geospatial data availability, following on the heels of volunteered geographical information. 相似文献
926.
927.
Alexandros A. Taflanidis Gaofeng Jia Andrew B. Kennedy Jane M. Smith 《Natural Hazards》2013,66(2):955-983
One of the important recent advances in the field of hurricane/storm modelling has been the development of high-fidelity numerical simulation models for reliable and accurate prediction of wave and surge responses. The computational cost associated with these models has simultaneously created an incentive for researchers to investigate surrogate modelling (i.e. metamodeling) and interpolation/regression methodologies to efficiently approximate hurricane/storm responses exploiting existing databases of high-fidelity simulations. Moving least squares (MLS) response surfaces were recently proposed as such an approximation methodology, providing the ability to efficiently describe different responses of interest (such as surge and wave heights) in a large coastal region that may involve thousands of points for which the hurricane impact needs to be estimated. This paper discusses further implementation details and focuses on optimization characteristics of this surrogate modelling approach. The approximation of different response characteristics is considered, and special attention is given to predicting the storm surge for inland locations, for which the possibility of the location remaining dry needs to be additionally addressed. The optimal selection of the basis functions for the response surface and of the parameters of the MLS character of the approximation is discussed in detail, and the impact of the number of high-fidelity simulations informing the surrogate model is also investigated. Different normalizations of the response as well as choices for the objective function for the optimization problem are considered, and their impact on the accuracy of the resultant (under these choices) surrogate model is examined. Details for implementation of the methodology for efficient coastal risk assessment are reviewed, and the influence in the analysis of the model prediction error introduced through the surrogate modelling is discussed. A case study is provided, utilizing a recently developed database of high-fidelity simulations for the Hawaiian Islands. 相似文献
928.
Lo?c Vanderkluysen Andrew J. L. Harris Karim Kelfoun Costanza Bonadonna Maurizio Ripepe 《Bulletin of Volcanology》2012,74(8):1849-1858
We collected thermal infrared video of two explosive eruptions at Stromboli in June 2008 and manually traced the trajectories of 95 particles launched during two eruptions. We found that 10–15?% of the analyzed trajectories deviated from predicted curves due to collisions, causing one particle to travel horizontally more than twice as far as expected. Furthermore, we observed an oscillatory cooling behavior for the airborne pyroclasts, with a median period of 0.46?s. Measured cooling was typically much faster than model-predicted cooling with discrepancies of up to 40?% between measured cooling and theoretical modeling. We interpret the measured cooling curves as resulting from the spinning and twisting and tearing of particles during travel: the periodic re-exposing of the hotter core of the pyroclasts to the atmosphere may cause the observed oscillations, and the spinning may accelerate cooling by enhancing convective heat transfer. Current volcanic trajectory and cooling models do not account for projectile collisions, spinning, or tearing and can thus severely underestimate the maximum landing distance and cooling rates of large pyroclasts. 相似文献
929.
Justina M. Burns William J. Cooper John L. Ferry D. Whitney King Brian P. DiMento Kristopher McNeill Christopher J. Miller William L. Miller Barrie M. Peake Steven A. Rusak Andrew L. Rose T. David Waite 《Aquatic Sciences - Research Across Boundaries》2012,74(4):683-734
This review summarizes direct and indirect analytical methods for the detection and quantification of the reactive oxygen species (ROS): 1O2, O 2 ·? /HOO·, H2O2, HO·, and CO 3 ·? in aqueous solution. Each section briefly describes the chemical properties of a specific ROS followed by a table (organized alphabetically by detection method, i.e., absorbance, chemiluminescence, etc.) summarizing the nature of the observable (associated analytical signal) for each method, limit of detection, application notes, and reaction of the probe molecule with the particular ROS. 相似文献
930.
Andrew Pennington Jonathon Smith Brad Koons Craig E. Divine 《Ground Water Monitoring & Remediation》2016,36(2):45-58
Light nonaqueous phase liquid (LNAPL) tracer testing is a technique used to directly measure LNAPL flow in situ and evaluate LNAPL mobility and recoverability. The test method consists of adding a fluorescent oil‐soluble tracer to LNAPL within a well, isolating small volumes of LNAPL with known tracer concentrations for use as in‐well calibration standards, and measuring the rate of tracer concentration decline in the well over time. The test measures LNAPL flux through the well, which is directly related to LNAPL mobility and recoverability in the surrounding formation. Test results for a total of 29 wells at five sites are presented. Results from LNAPL tracer testing were comparable to results obtained through other methods, and the method offers a time‐averaged result measured over a relatively long period, in ambient conditions, and reflects the influences of heterogeneity and hydraulic changes. In some cases, tracer concentration decline followed unexpected patterns, and these data have led to a better understanding of test assumptions, mechanisms influencing tracer distribution, and options to improve test execution and data interpretation. Method improvements developed over the course of the field studies included refinement of pre‐test screening of LNAPL fluorescence and improvements to measurement equipment. Overall, the field studies confirmed the technical validity and usefulness of the LNAPL tracing technique to support LNAPL mobility and recoverability assessments. 相似文献