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971.
M. W. Lake 《Journal of Archaeological Method and Theory》2014,21(2):258-287
This paper provides an up-to-date history of archaeological computer simulation, starting with the early 1970s simulation models, but paying particular attention to those developed over the past 20–25 years. It revises earlier accounts of archaeological simulation by proposing an alternation between programmatic phases, in which published work tends to be about simulation as a method, and mature phases in which there is greater emphasis on the substantive results of simulation experiments. The paper concludes that the burgeoning interest in computer simulation since circa 2000 is largely characterized by mature application in areas where it fits naturally into existing inferential frameworks (e.g., certain strands of evolutionary archaeology) but that explicitly “sociological” simulation remains a challenge. 相似文献
972.
973.
974.
Payam Tehrani Katsuichiro Goda Gail M. Atkinson Luc E. Chouinard 《Journal of Earthquake Engineering》2014,18(4):611-636
The seismic response of a continuous 4-span bridge designed according to the current Canadian seismic provisions is investigated using Incremental Dynamic Analysis (IDA). Different earthquake types, including shallow crustal events, interface Cascadia subduction, and deep inslab subduction are considered. The median collapse capacities calculated using different record selection methods including Conditional Mean Spectrum (CMS)-based, Uniform Hazard Spectrum (UHS)-based, and epsilon-based methods are compared. The use of the epsilon-based method generally resulted in the highest collapse capacity predictions, but the CMS-based method was less sensitive to the number of records considered in the IDA. 相似文献
975.
Jussi M. Hanhimäki 《Cold War History》2014,14(4):673-683
This article argues that the Cold War nostalgia of the present in the United States is ultimately based upon a poor – instrumentalist – reading of history. If anything, Cold War nostalgia shows the malleability of our present-day understanding of the past. 相似文献
976.
Structure‐ and tectonic‐related gas migration into Ordovician sandstone reservoirs and its impact on diagenesis history were reconstructed in two gas fields in the Sbaa Basin, in SW Algeria. This was accomplished by petrographical observations, fluid inclusion microthermometry and stable isotope geochemistry on quartz, dickite and carbonate cements and veins. Two successive phases of quartz cementation (CQ1 and CQ2) occurred in the reservoirs. Two phase aqueous inclusions show an increase in temperatures and salinities from the first CQ1 diagenetic phase toward CQ2 in both fields. Microthermometric data on gas inclusions in quartz veins reveal the presence of an average of 92 ± 5 mole% of CH4 considering a CH4‐CO2 system, which is similar to the present‐day gas composition in the reservoirs. The presence of primary methane inclusions in early quartz overgrowths and in quartz and calcite veins suggests that hydrocarbon migration into the reservoir occurred synchronically with early quartz cementation in the sandstones located near the contact with the Silurian gas source rock at 100–140°C during the Late Carboniferous period and the late Hercynian episode fracturing at temperatures between 117 and 185°C, which increased in the NW‐direction of the basin. During the fracture filling, three main types of fluids were identified with different salinities and formation temperatures. A supplementary phase of higher fluid temperature (up to 226°C) recorded in late quartz, and calcite veins is related to a Jurassic thermal event. The occurrence of dickite cements close to the Silurian base near the main fault areas in both fields is mainly correlated with the sandstones where the early gas was charged. It implies that dickite precipitation is related to acidic influx. Late carbonate cements and veins (calcite – siderite – ankerite and strontianite) occurred at the same depths resulting from the same groundwater precipitation. The absence of methane inclusions in calcite cements result from methane flushing by saline waters. 相似文献
977.
978.
Patrick Rérat 《Children's Geographies》2014,12(1):70-86
This paper addresses the motivations underlying migration decision-making in the case of young university graduates returning to their rural home region in Switzerland. Empirical results show the joint role of social ties, living environment, and job opportunities, although the weight given to each of these factors varies between graduates. Some strategies used by the graduates to cope with a limited labour market are furthermore identified. I argue that internal migrations are far from being the sole consequence of labour market conditions and that a greater appreciation of non-economic issues is needed. 相似文献
979.
S. Shalev E. N. Caspi S. Shilstein A. M. Paradowska W. Kockelmann T. Kan‐Cipor Meron Y. Levy 《Archaeometry》2014,56(2):279-295
Thirteen bronze battleaxes from Middle Bronze Age II graves at Rishon LeZion, Israel were analysed by ED XRF at multiple surface locations in order to determine their metallurgical composition. Six of these were further subjected to neutron diffraction using an ENGIN‐X diffractometer in order to determine bulk phase composition. The results indicate that the previously established geographical and chronological variability in Sn–Cu (with occasional Pb) and As–Cu alloys found using the former method may be an artefact of preservation and conservation. In addition, the varying homogeneity determined by the latter reflects special treatment for improving on the metal cast. 相似文献
980.
G. Huelga‐Suarez M. Moldovan M. Suárez Fernández M. Ángel de Blas Cortina J. I. García Alonso 《Archaeometry》2014,56(4):651-664
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing. 相似文献