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This essay will discuss the hegemonic role that texts have come to play in the historiography of subcontinental mathematical traditions. It will argue that texts need to be studied as records of practices of people's working lives, grounded in social hierarchies. We will take particular mathematical texts to show how different occupational registers have come to shape practices that defy the binaries of concrete and abstract, high and low mathematics or the pure and applied conundrum. Measuring, counting and accounting practices as part of the routine work of practitioners performing their caste occupations then provide us with a spectrum of the computational activities that controlled and regulated the lives of people in the past. In the process the act of computing itself gained certain political values such as cunning and manipulation, identified with professions of village accountant and merchant, for example. Drawn from my earlier work on these records, I discuss the occupational role of the accountant as a political functionary who assessed and authenticated the measurements of land and produce in the village, making values of the labor performed by others, and creating avenues for his own proficiency as a mathematical practitioner.  相似文献   
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Students at Stevens Institute of Technology (Hoboken, NJ, USA) investigated the reasons for an elongated projection at the bow of Mediterranean galleys. Using a 1:20 base model adapted from the Trireme Trust's Olympias fitted with: 1) an elongated projection; and 2) a control bow similar to excavated merchant ships, tow‐tank tests were carried out at various speeds. Hydrodynamic resistance and power were calculated for each bow type. Above speeds corresponding to 6 knots, the cutwater bow significantly attenuated the model's bow waves when compared to the control bow. These results were then compared to those of the ship with a ram‐type bow from experiments conducted in 1985 at the National Technical University of Athens, which showed similar wave‐attenuating characteristics.  相似文献   
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The Belgammel Ram was found off the coast of Libya in 1964, and examined during 2008–9. The following techniques were used: surface non‐contact digitizing using a laser scanner, reflectance transformation imaging using polynomial texture mapping and hemi‐spherical harmonics, digital photogrammetry with dense surface modelling, structured light optical scanning, and X‐ray fluorescence analysis. For internal structure the ram was examined by X‐radiography and 3‐D X‐ray tomography. Metallurgical composition was studied by micro‐drilling and subjecting the samples to scanning electron microscope X‐ray micro‐analysis, micro X‐ray fluorescence and X‐ray backscatter. The lead isotope composition was analysed. The alloy has average percentage composition Cu = 86.9, Sn = 6.3, Pb = 6.6, and Zn = < 0.10. The Belgammel Ram is probably a Hellenistic‐Roman proembolion from a small military vessel or tesseraria. The archived data are at the Faculty of Engineering and Environment, Engineering Sciences, Material Data Centre, University of Southampton ( muvis@soton.ac.uk ).  相似文献   
4.
Representations of ram‐like structures at the stern of warships mainly dating from the 5th century BC through to Late Antiquity suggest that ramming by the stern was an Illyrian tactic. When the Illyrian type of light warship, the liburnian, was introduced into Macedonian (?), Etruscan, and Roman navies, so apparently were rams. Coin images suggest a floruit in Late Roman fleets.  相似文献   
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