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31.
Karen Fisher Miriam Williams Stephen FitzHerbert Lesley Instone Michelle Duffy Sarah Wright Sandie Suchet‐Pearson Kate Lloyd Laklak Burarrwanga Ritjilili Ganambarr Merrkiyawuy Ganambarr‐Stubbs Banbapuy Ganambarr Djawundil Maymuru Bawaka Country 《New Zealand geographer》2015,71(1):18-33
This paper investigates the writing of situated knowledge and explores the possibilities of enacting difference by writing differently. We present a selection of research stories in which carrier bags, sounds, baskets, gardens and potatoes are interpreted less as objects of research or metaphors to aid in analysing phenomena, than as mediators of the stories. Our stories emphasise the ontological politics of engaging with and representing the relational, the messy, the spontaneous, the unpredictable, the non‐human and bodily experiences. These stories demonstrate how writing is performative and how it is integral to the production of knowledge. 相似文献
32.
Esperanza Muñoz‐Salinas Paul Bishop David CW Sanderson Jose‐Juan Zamorano 《地球表面变化过程与地形》2011,36(5):651-660
Optically stimulated luminescence (OSL) is a technique that has been applied from the mid‐1980s, mainly for sediment dating. The OSL technique is based on sample stimulation by light to determine the luminescence signal that is stored in the crystal lattices of sediment grains after deposition, burial by later sediment and subsequent exposure to ionizing radiation from radioactive elements in the surrounding sediment. In such sediment dating, two parameters are required: the equivalent dose (i.e. the luminescence signal stored in the grains), and the dose rate (i.e. the ionizing energy from α, β and γ radiation emitted by naturally occurring radioisotopes in the deposit, plus the effects of cosmic radiation). In this research, the OSL technique is not used for dating. The study goal is to analyse only the luminescence signals (the total photon counts) in polymineral samples obtained after light stimulation in the blue (BLSL) and infrared (IRSL) wavelengths using a portable OSL reader designed and built at the Scottish Universities Environmental Research Centre (SUERC). Three fluvial case studies – from Cambodia, Australia and Mexico – are used to illustrate the geomorphological interpretations possible with the portable OSL reader data from sediments resulting from a range of different depositional processes. The case studies show that aspects of sediment's transport and depositional processes can be inferred from the portable OSL reader data, providing valuable insights into geomorphological history. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
33.
Long-term degradation of optical devices on the Moon 总被引:1,自引:0,他引:1
Forty years ago, Apollo astronauts placed the first of several retroreflector arrays on the lunar surface. Their continued usefulness for laser ranging might suggest that the lunar environment does not damage optical devices. However, new laser ranging data reveal that the efficiency of the three Apollo reflector arrays is now diminished by a factor of 10 at all lunar phases and by an additional factor of 10 when the lunar phase is near full Moon. These deficits did not exist in the earliest years of lunar ranging, indicating that the lunar environment damages optical equipment on the timescale of decades. Dust or abrasion on the front faces of the corner-cube prisms may be responsible, reducing their reflectivity and degrading their thermal performance when exposed to face-on sunlight at full Moon. These mechanisms can be tested using laboratory simulations and must be understood before designing equipment destined for the Moon. 相似文献
34.
Side-scan sonars directed upwards from beneath the sea surface have been towed in waters off the west coast of Scotland. The sonographs show echoes from targets identified as subsurface bubble clouds produced by breaking wind-waves. In some conditions organised patterns are seen in the bubble clouds and, in particular, bubbles are accumulated in parallel rows by the effect of Langmuir circulations. The sonar is useful as a diagnostic tool to recognise and quantify these dynamical processes in the upper ocean boundary layer. 相似文献