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61.
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Since the 1980s, several experimental analyses have been able to differentiate some lithic tool types and some of their raw materials according to the morphology of cut marks imprinted by such tools when used for butchering activities. Thus, metal tool use has been differentiated in contexts with an abundance of lithic tools, or even the use of hand axes has been documented in carcass processing, in contrast with simple unretouched or retouched flakes. As important as this information is, there are still other important aspects to be analysed. Can cut marks produced with different lithic raw material types be differentiated? Can cut marks made with different types of the same raw material type be characterized and differentiated? The objective of this study is to evaluate if cut marks resulting from the use of different flints and different quartzites are distinguishable from each other. In the present work, an experimental analysis of hundreds of cut marks produced by five types of flint and five varieties of quartzite was carried out. Microphotogrammetry and geometric–morphometric techniques were applied to analyse these cut marks. The results show that flint cut marks and quartzite cut marks can be characterized at the assemblage level. Different types of flint produced cut marks that were not significantly different from each other. Cut marks made with Olduvai Gorge quartzite were significantly different from those produced with a set comprising several other types of quartzites. Crystal size, which is larger in Olduvai Gorge quartzites (0.5 mm) than Spanish quartzites (177–250 μm), is discussed as being the main reason for these statistically significant differences. This documented intra‐sample and inter‐sample variance does not hinder the resolution of the approach to differentiate between these two generic raw material types and opens the door for the application of this method in archaeological contexts.  相似文献   
63.
While interactive learning and inter-organizational relations are the fundamental building blocks in regional innovation system (RIS) theory, the framework is rarely related to investigations of regional knowledge network structures, because in RIS literature relational structures and interaction networks are discussed in a rather fuzzy and generic manner, with the “network term” often being used rather metaphorically. This paper contributes to the literature by discussing theoretical arguments about interactions and knowledge exchange relations in the RIS literature from the perspective of social network analysis. More precise, it links network-theoretical concepts and insights to the well-known classification of RIS types by Cooke [(2004) Introduction: Regional innovation systems – an evolutionary approach, in: P. Cooke, M. Heidenreich & H.-J. Braczyk (Eds) Regional Innovation Systems: The Role of Governances in a Globalized World, 2nd ed., pp. 1–18 (London: UCL Press)]. We thereby exemplarily show how the RIS literature and the literature on regional knowledge networks can benefit from considering insights of the respective other.  相似文献   
64.
65.
The remains of a coasting vessel were found in a lagoon close to the coast. Four radiocarbon determinations provided a date in the mid-15th century and it has been the subject of several seasons of excavation of CNANS. The excavation strategy is described, as are its surviving constructional details which are analysed with reference to early sources for Portuguese naval architecture. This coaster has constructional features found in ocean-going ships of the Iberian-Atlantic tradition. Its cargo of pottery is one of the most extensive and closely dated from the Age of Discovery and includes 18 forms.  相似文献   
66.
Transport infrastructure is considered one of the main policy instruments to achieve the cohesion goal, although the inclusion of cohesion effects in assessment methodologies is scarce and uneven. Although most cohesion studies are constrained to the analysis of regional disparities in economic indicators, this approach can be broadened to include other regional performance indicators. One of these indicators could be accessibility measures, from the point of view that accessibility, representing a competitive advantage of locations, constitutes a “desirable good” closely related to the welfare of each region. This paper suggests using changes in the spatial distribution of accessibility as a proxy to assess regional cohesion effects of transport infrastructure investments. However, as the conclusions taken depend heavily on the formulation of the accessibility measure, we recommend computing a set of accessibility indicators and analysing their results in a complementary way. The proposed methodology is tested by assessing regional cohesion effects of the large-scale road and rail transport infrastructure investments carried out in Spain in the period 1992–2004. The results obtained show that cohesion has improved for the road mode, while regional disparities have increased for the rail mode. This paper identifies the main factors driving this final cohesion effect and explores the strengths and weaknesses of the different accessibility indicators that were considered. The approach suggested in this paper has the potential to be applied in transport planning processes, and may eventually complement existing strategic assessment methodologies.  相似文献   
67.
A huge monolithic piece corresponding to the first years of the sixteenth century has been discovered in Mexico City. It represents the earth goddess Tlaltecuhtli. The preservation of such a magnificent piece is imperative. Therefore, the surface has to be characterized and the interaction of consolidants with the rock has to be understood.Some of the consolidation methods are impregnation of the mineral with nopal or silicic acid derivatives. In this work we compare the physico-chemical effects of organic and inorganic consolidants. Original and impregnated samples are characterized with a series of original techniques: X-ray diffraction, nuclear magnetic resonance, nitrogen adsorption and small angle X-ray scattering. Fractal dimension, specific surface area and pore size distribution clearly differentiated the samples. The organic materials, nopal gum or slobber, cover the mineral particles with a smooth layer. The KSE solutions react and lead to microporosity.  相似文献   
68.
Water management and population issues have always been particularly important in Spain, a country historically characterized by severe environmental constraints on agricultural growth and intense rural depopulation. This paper evaluates whether irrigation projects in Spain over the course of the twentieth century have achieved one of their main objectives, which was to reduce rural population decline. This paper makes two contributions. First, we compare the evolution of population in two of the earliest and most ambitious irrigation projects in Spain, the Riegos del Alto Aragón (Upper Aragon Irrigation System) and the Canal de Aragón y Cataluña (Aragon and Catalonia Canal System), both located in the Ebro basin. Second, the time period of the study spans an entire century. This long-term approach is crucial if we accept that irrigation requires time to consolidate its effects and, therefore, its impact on population may be long delayed. We show that the evolution of population in each of the two projects has been substantially different. We also analyze the factors that have caused or prevented population growth. We argue that financial, economic and environmental limitations have been significant, but also that political and geographical factors have played a major role.  相似文献   
69.
The objective of this paper is to obtain several poverty reduction effects by using multipliers based on social accounting matrices. Expressions relating them to Foster, Greer and Thorbecke poverty measures were derived, and two simulations were carried out for the Spanish region of Extremadura. In the first, we posited a per capita transfer equivalent to certain social policy instruments already existing in this region. Structural path analysis is also used to determine the paths by which poverty reduction effects are transmitted. In the second, we calculate the minimum government expenditure in transfers needed to reduce the regional poverty indices to the national values. The results confirmed that the main feature of poverty in Extremadura is incidence.  相似文献   
70.
This article makes a contribution to the study of the role of regional authorities in the process of regional development by analyzing the case of the Valencia region, a Spanish peripheral region whose economic success was historically dependent upon the maintenance of low labour costs in traditional artisan manufacturing activities. This led to an extreme focus on products of poor quality. In order to overcome this situation, Valencian regional authorities have launched an important number of policies that aim at solving two of the most important weaknesses of the regions: the high dependence on a few manufacturing activities, and the lack of a technology policy that could help to enhance the quality of the Valencian products. The analysis of the measures adopted by the regional authorities in the region of Valencia is expected to be of interest for other peripheral regions characterized by a similar situation—i.e. a traditional lack of interest in technology and innovation.  相似文献   
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