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The use of renewable hydraulic energy sources by mankind most likely has its origins in the development of the watermills. To understand the functioning of these mills, this article first reviews, through the analysis of different bibliographical sources, the technical evolution of the machinery used since the appearance of the first watermills to grind cereal grain in the 1st century bc.

Secondly, a particular area of the south-west of Spain, Alcalá de Guadaíra, has been selected for study, whose strategic location as well as its hydrological characteristics gave rise, firstly, to an intensive milling industry, and, later, a famed baking industry, from the late Middle Ages until recent decades. The huge development of these two industrial activities has made Alcalá de Guadaíra an exceptional example in Spain, with 40 watermills in the early 18th century.

Extensive work on site allowed the analysis of the state and types of watermills that still exist in this area, identifying their similarities and differences. Unfortunately, after they fell into disuse, only 28 of these mills remain today; 12 of them are in a relative good state of preservation, seven in an alarming state of ruin and, of the other nine, only some unrecognisable vestiges remain. Some of these mill buildings have been restored recently, although their machinery is missing. Only from old photographs or by visiting mills restored in other areas is it possible to determine how these watermills worked.

Due to the lack of financial resources to carry out physical restoration of the industrial heritage missing in these flour mills, a virtual model of one of them has been developed. This work provides, at least virtually, a reconstruction of the traditional mills which helps promote technological studies and shows how they worked, as part of virtual exhibitions. In addition, a computer application of augmented reality has been developed that any visitor can install on a mobile device to display the virtual reality of the machinery, generated by 3D models, so they can visualise the physical reality that they would have found in the mill.  相似文献   

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Portugal was the second country in Western Europe to ratify the 2001 UNESCO Convention, a pivotal step that occurred on September 21, 2006. In 2000 the Portuguese delegation presented a statement in the UNESCO meeting for the draft Convention, the substance of which emphasises the protection and cooperation principles concerning the underwater cultural heritage rather than the issue of its possession. In 2008, the discovery of a sixteenth century Portuguese shipwreck near Oranjemund, Namibia, confirmed that the referred statement opened a premonitory strategic window for the conciliation of interests of States around such examples of common heritage.  相似文献   
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ABSTRACT In industrializing regions, foreign investments often generate spillovers through regional backward links. This situation may create a gap between private and social valuations of resources, resulting in a level of local content below what would be optimal for the economy. This situation creates an opportunity for the enactment of domestic content regulations. This paper presents a model to understand how these policies condition the decisions of the economic agents and affect economic welfare. Then, it simulates the model using a case study of the automotive sector. Results suggest that, in certain conditions, this local content regulation can be welfare enhancing.  相似文献   
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Journal of Maritime Archaeology - This study analyses nautical harbour activities and their spatial distribution using a high-resolution method of wind-wave hindcasting, in order to identify the...  相似文献   
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This article proposes an interpretation of Lope de Vega's El Brasil Restituido (1625) that points to the political, military, and economic crises of Spain in Europe as the underlying themes of the representation of the retaking of the Brazilian colony of Bahía from the Dutch. The Spanish monarchy faced a major challenge to its European supremacy during the first two decades of the seventeenth century. Not only was its military power being frontally contested at different sites of Europe, but its political and economic influence was rapidly deteriorating as well. One of the goals of the Count-Duke of Olivares, the powerful prime minister of Phillip IV, was to regain European leadership by mobilizing the mercantile segments of Spain. The play illustrates the confluence of two ideological systems during the transformation of Spanish feudal society. On the one hand, the dominant ideology of blood purity legitimizes the seigniorial structure of lineage; on the other hand, the representation of a new merchant as a good servant of the king discloses the important role that a mercantile enterprise and ethos had acquired in the formation of a subject to the monarchy.  相似文献   
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Why do societies implement land policies? A number of arguments have been put forward in the literature, ranging from economic conceptions based on market failure and the problem of negative externalities to a more social conception based on welfare distribution and collaborative planning. However, neither all societies with similar market failures or negative externalities develop and implement land planning nor implemented land planning always results from collaborative planning. The arguments found in the literature seem not to fit the reality and, in most cases, cannot explain why societies create or undertake innovations in land planning. Within the framework of institutional change theory and based on the analysis of the emergence of two land planning devices—a land use law and a land banking law—in Galicia, Northwest Spain, this paper argues that land planning is developed to tackle negative outcomes of former institutional setups. However, the negativity of such outcomes is measured not in terms of economic performance, but in terms of social acceptance. The search for a workable definition of property within the Galician society seems to be the main driver of institutional change in land use planning analysed in this paper.  相似文献   
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We synthesize and discuss available isotopic data on Holocene guanaco samples from southern South America, extending from Tierra del Fuego Island to northern Patagonia and the Pampean region. We evaluate temporal and spatial tendencies on the basis of 91 samples (mainly based on δ13Ccollagen values), presenting implications for paleodietary research in archaeology. We conclude that there are no strong correlations with latitude in the macro-spatial scale, while there is a set of interesting patterns at smaller regional scales. These patterns lead us to evaluate the role of ecologic and topographic variables (e.g. canopy effect, variations in altitude, ecotones) in structuring isotopic variability. Finally, on the basis of the present analysis we suggest a number of hypotheses and perspectives for the use of stable isotopes as geographic tracers of guanaco distribution in the past, and specific implications for the paleodietary study of human samples.  相似文献   
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