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ABSTRACT This paper considers a location model to illustrate the effect of zoning on competition. A planner is in charge of designing a city in a circular space where firms and consumers are located on different sides. With this type of market configuration, equilibrium in location under concave transport costs is proved. Then, a welfare function with different weights attached to consumer and firm surpluses is introduced to highlight zoning regulation as an influential competition policy tool. Depending on the regulator's political profiles and the demand, it is shown that zoning can lead to strong, weak, or moderate competition. 相似文献
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Sourcing ceramics with portable XRF spectrometers? A comparison with INAA using Mimbres pottery from the American Southwest 总被引:1,自引:0,他引:1
Robert J. Speakman Nicole C. Little Darrell Creel Myles R. Miller Javier G. Iñañez 《Journal of archaeological science》2011,38(12):3483-3496
Seventy-five intact Mimbres and Jornada pottery sherds from the American Southwest were analyzed by portable XRF and instrumental neutron activation analysis (INAA). Examination of the data demonstrates that INAA and portable XRF results for elements common to both analyses can be used to construct similar compositional groups. When individual compositional groups are compared to one another, it is apparent that unambiguous separation of compositional groups is challenging by portable XRF given (1) the limited number of key discriminating elements that can be measured relative to INAA, and (2) the relative analytical precision and accuracy of portable XRF for measurements of intact heterogeneous ceramics. We conclude that sourcing intact ceramics by portable XRF is challenging and that bulk analytical measurements, such as INAA, remain a better approach for sourcing archaeological pottery. 相似文献
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Frontini Romina Roselló-Izquierdo Eufrasia Morales-Muñiz Arturo Denys Christiane Guillaud Émilie Fernández-Jalvo Yolanda Pesquero-Fernández María Dolores 《Journal of Archaeological Method and Theory》2022,29(2):480-507
Journal of Archaeological Method and Theory - Fish taphonomy from archaeological sites provides considerable useful information about human behaviours and environmental contexts as potential food... 相似文献
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Virginia García-Marín Pablo García-López Miguel Freire 《Journal of the history of the neurosciences》2013,22(2):197-210
Abstract Multiple sclerosis (MS) was first presented in a clinical setting in 1838. In this paper the presentation and treatment of a transient hemiparesis in a drummer in 1789 is discussed. This may have been an early case of MS and presents evidence against the theory that MS is an infectious disease beginning in the 19th century. 相似文献
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Tiina Väre Juho-Antti Junno Jaakko Niinimäki Markku Niskanen Sirpa Niinimäki Milton Núñez 《Post-Medieval Archaeology》2013,47(2):368-379
Summary: Mummified human remains have been preserved in the cool, well-ventilated crypts of old Finnish churches, which were popular burial sites among the elite of the early modern period. Here, the authors present the results of a computed tomography study of the remains of an early 17th-century vicar of Keminmaa. They examined the preservation of his remains and made several pathological findings; the causes of the latter possibly had a severe impact on his health. He was a large man who achieved relative longevity for his time, although he suffered from conditions related to obesity. There were also potential indications of tuberculosis. Inflammatory changes, for example, had afflicted his spine. 相似文献
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Matthew C. Pailes Natalia Martínez-Tagüeña William H. Doelle 《Journal of Field Archaeology》2013,38(8):619-633
This article demonstrates the relevance of future discounting behavior to studies of prehistoric subsistence strategies. The case study of Agave spp. bajada cultivation among the Classic Period, a.d. 1150–1450, Hohokam of southern Arizona illustrates how slight discounting of future rewards can significantly alter agriculture investment strategies. Despite a higher kcal/hour return than maize agriculture, agave cultivation lessened or ceased in several communities during a time in which intensification would be predicted due to inferred subsistence stress. We surmise the decade-long maturation of agave made it unattractive relative to more immediate return resources in any context that presented risks to land tenure. The cessation of agave cultivation can be understood on two levels of explanation. The long-term investments required by agave and tendency to discount future rewards are the ultimate causes. Political and social instability during the tumultuous Classic period, causing increased insecurity in land tenure, are the proximal causes. 相似文献
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A review of archaeobotanical data, together with new, still unpublished data, from Roman sites in conventus Bracaraugustanus suggests the Romanization of the northwest Iberia brought little changes to the agricultural strategies of local communities in indigenous-type settlements. The main crops remain the same as in the Iron Age: Triticum aestivum/durum, Panicum miliaceum, Hordeum vulgare subsp. vulgare, Triticum turgidum subsp. dicoccum and T. aestivum subsp. spelta, Avena and Vicia faba. The first secure reference for the cultivation of Secale cereale in the region comes from a Roman context, suggesting that it was introduced in this period, although it probably remained a minor crop. 相似文献