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141.
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Peter A. Rogerson Eric Delmelle Rajan Batta Mohan Akella Alan Blatt Glenn Wilson 《Geographical analysis》2004,36(2):177-194
It is often desirable to sample in those locations where uncertainty associated with a variable is highest. However, the importance of knowing the variable's value may vary across space. We are interested in the spatial distribution of Received Signal Strength Indicator (RSSI), a measure of the signal strength from a cell tower received at a particular location. It is crucial to estimate RSSI values accurately in order to evaluate the effectiveness of mayday systems designed for rapid emergency notification following vehicle crashes. RSSI estimation is less important for locations where the probability of a crash is low and where the likelihood of call completion is either close to zero or one. We develop a method for augmenting an initial spatial sample of RSSI values to achieve a high‐precision estimate of the probability of call completion following a crash. We illustrate the approach using data on RSSI and vehicle crashes in Erie County, NY. 相似文献
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Peter Bleed 《Journal of Archaeological Method and Theory》2008,15(1):154-166
Skill is a challenging topic for archeologists because it requires balancing the biases of cultural relativity with the commonsense
understanding that some humans are more able than others. Using the content and results model of technology, this paper identifies
skill as a variable of technological knowledge with recognizable material results. Late Paleolithic Japanese blade and microblade
assemblages suggest that skill differentials exist on the cognitive, operational, and motor levels. These examples, together
with ethnoarcheological consideration of modern potters suggest material reflections of technical skill. These include regularity
in performance and product, skilled tools, and obvious signs of practice. 相似文献
145.
Peter D. Little John McPeak Christopher B. Barrett Patti Kristjanson 《Development and change》2008,39(4):587-611
Understanding and alleviating poverty in Africa continues to receive considerable attention from a range of diverse actors, including politicians, international celebrities, academics, activists and practitioners. Despite the onslaught of interest, there is surprisingly little agreement on what constitutes poverty in rural Africa, how it should be assessed, and what should be done to alleviate it. Based on data from an interdisciplinary study of pastoralism in northern Kenya, this article examines issues of poverty among one of the continent's most vulnerable groups, pastoralists, and challenges the application of such orthodox proxies as incomes/expenditures, geographic remoteness, and market integration. It argues that current poverty debates ‘homogenize’ the concept of ‘pastoralist’ by failing to acknowledge the diverse livelihoods and wealth differentiation that fall under the term. The article concludes that what is not needed is another development label (stereotype) that equates pastoralism with poverty, thereby empowering outside interests to transform rather than strengthen pastoral livelihoods. 相似文献
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There is more woodland in Britain now than for many centuries and considering many international climate change mitigation policies, woodland cover, both in Britain and internationally, is being promoted. However, neither the management of existing woodlands nor their expansion should be at the expense of important archaeological evidence. Due to the large number of known archaeological sites, the large areas of land with uninvestigated archaeological potential and the expanding woodland cover, suitable mitigation strategies need to be developed to allow preservation in situ of important sites. An understanding of how woodland soils and the buried archaeological resource interact is, therefore, essential. This paper utilises ongoing environmental research into the mineral weathering rates in forest soils and considers its application to artefact preservation. The study concludes that soil water pH, its movement, and the saturation of dissolved ions in the soil solution are major factors determining both mineral and artefact longevity. A simple guide to artefact longevity based on these properties is proposed and a geochemical model for predicting loss is tested. These tools could be applied to any soil or individual horizon irrespective of land-use. 相似文献
149.
David R. Braun Thomas Plummer Peter Ditchfield Joseph V. Ferraro David Maina Laura C. Bishop Richard Potts 《Journal of archaeological science》2008
The archaeological record of Oldowan hominins represents a diverse behavioral system. It has been suggested that exploitation of lithic resources by Oldowan hominins was simplistic and represented mostly use of local sources of stone. Here we investigate the raw material selection and transport behaviors of Oldowan hominins reflected in the stone artifact assemblages from the Kanjera South Formation, South Rachuonyo District, Kenya. Using geochemical methods (ED-XRF) artifacts are linked to primary and secondary source outcrops throughout southwestern Kenya. These data show that hominins selected raw materials for transport at frequencies that are significantly different from their availability on ancient landscapes. Furthermore, a substantial proportion of the assemblage represents transport over relatively long distances (>10 km). Our study further suggests that in the early stages of stone tool use hominins used a wide variety of raw materials and selected these materials at some distance from their eventual discard locations. Early hominin behavior may have incorporated an understanding of raw material source distributions across a more extensive landscape than has been previously documented. This supports the growing perspective that Oldowan technology represents a more complex behavioral pattern than is usually associated with the beginnings of hominin tool use. 相似文献
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