1,814 research outputs found

    Infrared Television Used to Detect Hydrogen Fires

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    Standard, commercially available closed circuit television system detects hydrogen fires in test facilities. It sees in the infrared and displays on a standard cathode ray monitor screen

    Modeling a primate technological niche

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    The ability to modify the environment through the transport of tools has been instrumental in shaping the evolutionary success of humans. Understanding the cause-and-effect relationships between hominin behavior and the environment ultimately requires understanding of how the archaeological record forms. Observations of living primates can shed light on these interactions by investigating how tool-use behaviors produce a material record within specific environmental contexts. However, this requires reconciling data derived from primate behavioral observations with the time-averaged nature of the Plio-Pleistocene archaeological record. Here, we use an agent-based model to investigate how repeated short-distance transport events, characteristic for primate tool use, can result in significant landscape-scale patterning of material culture over time. Our results illustrate the conditions under which accumulated short-distance transport bouts can displace stone tools over long distances. We show that this widespread redistribution of tools can also increase access to tool require resources over time. As such, these results elucidate the niche construction processes associated with this pattern of tool transport. Finally, the structure of the subsequent material record largely depends on the interaction between tool transport and environmental conditions over time. Though these results have implications for inferring hominin tool transports from hominin archaeological assemblages. Furthermore, they highlight the difficulties with connecting specific behavioral processes with the patterning in the archaeological record

    Identifying functional and regional differences in chimpanzee stone tool technology

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    The earliest hominin archaeological sites preserve a record of stone tools used for cutting and pounding. Traditionally, sharp-edged flakes were seen as the primary means by which our earliest ancestors interacted with the world. The importance of pounding tools is increasingly apparent. In some cases, they have been compared with stone hammers and anvils used by chimpanzees for nut-cracking. However, there has been little focus on providing a robust descriptive and quantitative characterization of chimpanzee stone tools, allowing for meaningful comparisons between chimpanzee groups and with archaeological artefacts. Here we apply a primate archaeological approach to characterize the range of chimpanzee nut-cracking stone tools from Djouroutou in the Taï National Park. By combining a techno-typological analysis, and two- and three-dimensional measures of damage, we identify clear differences in the location and extent of damage between nut-cracking hammerstones and anvils used at Djouroutou and when compared with other wild chimpanzee populations. Furthermore, we discuss these results in relation to interpretations of Plio-Pleistocene percussive technology. We highlight potential difficulties in identifying the underlying function of percussive artefacts based on morphological or techno-typological attributes alone. The material record from Djouroutou represents an important new datum of chimpanzee regional and material culture

    A biomechanical invariant for gait perception.

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    Use-wear and residue analysis of pounding tools used by wild capuchin monkeys (Sapajus libidinosus) from Serra da Capivara (Piauí, Brazil)

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    Bearded capuchin monkeys (Sapajus libidinosus) from Serra da Capivara National Park (Brazil), perform the widest range of activities using stone tools of all the non-human tool-using primates. The behaviours behind this range of tool-use have been closely documented, but little is known about the characteristics of the tools themselves. Here we redress this imbalance and adopt an archaeological perspective to the analysis of capuchin pounding tools. We apply, for the first time, systematic microscopic techniques to the analysis of capuchin stone tools used for digging, cracking cashew nuts and seed processing to characterise their damage patterns combined with residue spatial distribution and micro-remains analysis. This work presents a standardized methodology for future primate archaeological use-wear studies as well as forming a reference collection which can be used to identify different activities within the primate archaeological record. Furthermore, understanding the archaeologically visible traces of primate percussive behaviours represents an initial step in developing a methodology to investigate if similar activities were practiced by early hominins and to help identify these activities in the Plio-Pleistocene archaeological record

    Improvements to the Indiana Geological Survey’s Petroleum Database Management System

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    This poster was presented at the 2011 Annual Meeting of the American Association of Petroleum Geologists, Eastern Section, in Arlington, Virginia, in September 2011.The Indiana Geological Survey’s Petroleum Database Management System (PDMS) is a web application that provides online access to petroleum-related geological information. Since its debut in 2004, the application has been widely used by the petroleum industry, academia, government agencies, and the general public. On June 6, 2011, a significantly enhanced version of the PDMS went online. New features include a robust search menu that permits elaborate queries of more than 74,000 petroleum wells, rapid and convenient online viewing and downloading of PDF-file well reports and both PDF- and TIFF-file geophysical and other well logs, and streamlined menus for easily accessing extensive well data. An interactive, context-driven web help explains every concept or term used. The PDMS is organized in three main sections. The Well Tables Section includes such information as well location descriptions, completion zones, logs, operators, lease names, tests, reports, hydrocarbon shows, samples, cores, geologic formations and tops, and directional survey data. The Map Viewer Section contains many user-selectable layer options for showing well locations, petroleum fields, producing formations, aerial photographs, and topographic maps. Wells shown in the Map Viewer are hyperlinked to the Well Tables for easy access to the well data. The Fields and Production Section summarizes oil, natural gas, and gas storage field data, including historical oil production volumes in both tables and charts

    The impact of hydraulic processes in Olduvai Beds I and II, Tanzania, through a particle dimension analysis of stone tool assemblages

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    The effect of post-depositional processes on the formation of Plio-Pleistocene sites at Olduvai Gorge is the subject of considerable debate, due mainly to its implications for the behavioral interpretation of the Beds I and II assemblages. In light of this debate, here we contribute to the discussion that investigates the role of water flow in site formation at Olduvai. This is achieved by assessing the artifact size and shape ranges of lithic assemblages excavated by Mary Leakey from both Oldowan (FLK North Levels 3 and 1, FLK Zinj, FLK North Levels 6-1, Sandy Conglomerate and Deinotherium, HWKE Level 1) and early Acheulean (TK Lower and Upper Floor) sites. We apply grain size and shape statistical techniques to these stone tool assemblages in order to classify sites according to patterns in artifact dimensions. These patterns are then compared to those produced during experimental flaking, thus providing a referential framework against which the archaeological assemblages can be interpreted. Artifact size distribution results show pronounced differences between the archaeological and experimental assemblages. Most of the archaeological assemblages are characterized by a bimodal size trend that is opposed to the dominantly unimodal distribution seen in the flaking experiments. The few archaeological assemblages where the distribution is predominantly unimodal (TF Lower Floor, TK Upper Floor and FLK Zinj) also show a significant underrepresentation of smaller artifacts, when compared to the experimental distributions. Overall, the comparison of archaeological materials with experimental results enables a more accurate assessment of the impact of natural processes over the Bed I and II assemblages, and further, it helps to refine our understanding of taphonomic and behavioral contexts for the Oldowan and early Acheulean sites at Olduvai Gorge

    Towards Real-World Applications of ServiceX, an Analysis Data Transformation System

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    One of the biggest challenges in the High-Luminosity LHC (HL- LHC) era will be the significantly increased data size to be recorded and analyzed from the collisions at the ATLAS and CMS experiments. ServiceX is a software R&D project in the area of Data Organization, Management and Access of the IRIS- HEP to investigate new computational models for the HL- LHC era. ServiceX is an experiment-agnostic service to enable on-demand data delivery specifically tailored for nearly-interactive vectorized analyses. It is capable of retrieving data from grid sites, on-the-fly data transformation, and delivering user-selected data in a variety of different formats. New features will be presented that make the service ready for public use. An ongoing effort to integrate ServiceX with a popular statistical analysis framework in ATLAS will be described with an emphasis of a practical implementation of ServiceX into the physics analysis pipeline.Comment: 8 pages, 3 figures, 2 listings, 1 table, submitted to the 25th International Conference on Computing in High Energy & Nuclear Physic

    Distance-decay effect in stone tool transport by wild chimpanzees

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    Stone tool transport leaves long-lasting behavioural evidence in the landscape. However, it remains unknown how large-scale patterns of stone distribution emerge through undirected, short-term transport behaviours. One of the longest studied groups of stone-tool-using primates are the chimpanzees of the Taï National Park in Ivory Coast, West Africa. Using hammerstones left behind at chimpanzee Panda nut-cracking sites, we tested for a distance-decay effect, in which the weight of material decreases with increasing distance from raw material sources. We found that this effect exists over a range of more than 2 km, despite the fact that observed, short-term tool transport does not appear to involve deliberate movements away from raw material sources. Tools from the millennia-old Noulo site in the Taï forest fit the same pattern. The fact that chimpanzees show both complex short-term behavioural planning, and yet produce a landscape-wide pattern over the long term, raises the question of whether similar processes operate within other stone-tool-using primates, including hominins. Where hominin landscapes have discrete material sources, a distance-decay effect, and increasing use of stone materials away from sources, the Taï chimpanzees provide a relevant analogy for understanding the formation of those landscapes
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