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M.-C. Gerbet 《Journal of Medieval History》1991,17(4)
Despite a few pioneering studies into transhumant raising in the kingdom of Castile much work in this field has yet to be done. We are acquainted with its general organisation but more rarely with its local manifestations. On the whole we know of the revenues it yielded to the Crown but less of those it delivered to the lords. It was during a lawsuit brought by the Mesta at the end of the fifteenth century against the lord of Capilla, whom it accused of imposing illegal taxes upon the migration of the winter herds across the Capilla bridge on their way to the Extranadura of the south, that a rich documentation was collected by the incriminated party. This documentation holds a twofold interest for us: first it informs us about the region of origin of the animals which followed this migration, the number of herds involved, their composition and their owners and shepherds; second it gives us knowledge of the revenues which a lord could extract from the collection of taxes imposed on the migration, or transhumance, itself. 相似文献
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Is the Suburban Railway System a Fractal? 总被引:2,自引:0,他引:2
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While research has tackled the hub-and-spoke network design problem, that research has overlooked the air-truck modal integration issue which is a common feature of real express delivery systems. This paper devises integer linear programs to represent the mode and route assignment aspects of the operational problem. The model is solved under four different levels of delivery schedule, and the results show that as the promised delivery schedule is relaxed, not only does the use of truck routes become more desirable, but also interesting adjustments in mode and hub assignment occur. Consider the case of hubs in Los Angeles and Dayton. As the time constraints are relaxed, cities such as Minneapolis and New Orleans originally linked by air to Los Angeles, switch to Dayton because cheaper truck routes become feasible. 相似文献