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121.
Cut mark frequencies in archaeological faunal assemblages are so variable that their use has recently created some skepticism. The present study analyses this variability using multivariate statistics on a set of 14 variables that involve differential skeletal element representation, fragmentation processes, carnivore ravaging impact, carcass size and tool type. All these variables affect the resulting cut mark frequencies reported in archaeological sites. A large sample of archaeofaunal assemblages has been used for this study. It was concluded that the best estimator of cut mark frequency in any given assemblage is the percentage of cut-marked long bone specimens (probably due to its better preservation than other anatomical areas), which is determined by fragmentation and carnivore ravaging. Carcass size and tool type also play a major role in differences in cut mark frequencies. Fragmentation is also a key variable determining the abundance of cut-marked specimens. It is argued that general cut mark percentages are of limited value, given the number of variables that determine them, and that a more heuristic approach involves quantifying cut marks in a qualitative manner.  相似文献   
122.
Stone masonry walls of ancient buildings have reasonable resistance to vertical loads but lower resistance to shear forces and reduced tensile strength. However, to achieve such compressive strength the masonry must not disaggregate when subjected to loading. This can be achieved if during the construction of the walls larger stones, usually referred as “through stones”, are used, spanning the thickness of the wall, making it possible to improve the transverse confinement of the masonry. For rehabilitation projects and structural reinforcement of such buildings, the transverse confinement can be achieved by fixing steel elements perpendicular to the wall. This confinement technique is often part of a more comprehensive rehabilitation solution, which includes the application of mortar or concrete reinforced layers applied to the wall surface.

This article presents results of an experimental research on material properties and mechanical characterisation of stone masonry specimens strengthened by two transverse confinement solutions (independent steel reinforcing rods and continuous steel ribbons wrapping the specimen). Specimens were tested under compression and compression and shear loadings.

This experimental work is part of a major research project to study the mechanical behavior of URM and strengthened walls, and the characteristics of the building materials of such specimens.  相似文献   

123.
Traditional taphonomic analyses do not consider the emergent properties resulting from the relationship of variables. Several of these emergent properties are expressed spatially. Here, we present a spatial taphonomic approach to the understanding of post-depositional processes affecting experimental assemblages modified by fluvial currents. Spatial statistical methods are a great tool to understand how different taphonomic variables relate at a spatial scale. The results of the application of this method to bone assemblages affected by low- and high-energy flows show the loss or modification of most of the original spatial taphonomic relationships. It also shows the degree of bone loss according to element, anatomical section and bone structure, and shape types. Anisotropy is identified in both experimental contexts. These results add new criteria to assess the impact of water flows in bone assemblages and contribute to define the properties of lag assemblages.  相似文献   
124.
The recent increase in business services in terms of both value added and employment has had a positive effect on regional economies, helping them to create a comparative advantage and contributing to the general development of regional productive systems. This heterogeneous set of activities is characterized, among others, by its uneven distribution in the territory. In this paper we aim to identify the key factors that influence the location of business services within the NUTS 2 regions of the European Union. Using a multivariate analytical approach (combining a principal components factor analysis and a multiple linear regression by means of ordinary least squares), four key factors have been identified. In terms of their influence on the location of business services, we can pinpoint the following factors: urban dimension, competitiveness, accessibility and economic dynamism. It was found that business services tend to locate in urban, densely populated and dynamic areas with high levels of competitiveness and easy access.  相似文献   
125.
This paper examines the evolution of regional innovation policy in Emilia-Romagna and Valencia, two regions with similar economic features that implemented close innovation policies in the 1970s and 1980s. We investigate whether their similarities have led to parallel targets, policy tools and governance developments. We show that innovation policy in both regions suffered from the effects of privatization, budget constraints and changes to manufacturing during the 1990s and we highlight the consequences. Although Emilia-Romagna experienced deeper changes to its innovation policy, privatizations and/or the replacement of public funds promoted commercial approaches and induced market failures in both regions. The worst effects of these policies were the implementation of less-risky innovation projects, the shift towards extra-regional projects and markets, and the favouring of large firms.  相似文献   
126.
This paper analyses the effects of R&D expenditure in the higher education sector on the scientific production across regions in Europe 15. Our research questions relate to the regional production of science and the role of academic R&D expenditures on regional scientific output. The results show that money affects the production of scientific results in regions. On average, we found different impacts and lags of R&D expenditure according to the level of regional development. Our findings also suggest that scientific specialization is a significant factor affecting scientific outputs, although its effects differ across disciplines and regions.  相似文献   
127.
This article examines Preclassic Maya ritual practices and craft production by means of a study of ritual deposits containing obsidian artifacts dated mostly to the late Middle Preclassic period (700–350 b.c.) at Ceibal, Guatemala. New ritual practices developed at Ceibal during this period, possibly through political interactions and negotiation involving emerging elites and other diverse community members. Common objects in ritual deposits in the public plaza shifted from greenstone celt caches to other artifacts, including those made of obsidian. The inhabitants of Ceibal engaged in various kinds of craft production, including the manufacture of obsidian prismatic blades. They also conducted public rituals in the Central Plaza, depositing exhausted polyhedral obsidian cores and other artifacts with symbolic significance in caches and as offerings in incipient elite burials and interments of sacrificed individuals. These cores clearly demonstrate the use of a sophisticated blade technology. Like greenstone objects, exhausted polyhedral obsidian cores deposited in cruciform arrangements along the east–west axis of the central E-Group plaza were used as symbols and markers of the center and four cardinal directions within the Maya cosmos. Public rituals were important for creating collective identities and for processes of political negotiation within the community. Emerging elites likely came to play an increasingly important role in public rituals as principal performers and organizers, setting the stage for later public events centered on rulers.  相似文献   
128.
There have been significant territorial changes in the Spanish Mediterranean in the last few decades because of the important growth of residential tourism functions. The Spanish National Hydrological Plan ( 2001 ) and, to a greater extent, the Action for Management and Use of Water Programme ( 2004 ) advocated large‐scale desalination of seawater to guarantee a supply for urban, tourism, and even future agricultural demands. The paralysis of urban development planning caused by the financial crisis (2007/08), together with the downward trend in the consumption of drinking water in the last decade, highlighted a capacity to produce desalinated water that was far superior to actual needs. This study reviews the current context in which desalinated water is produced in Spain, weighs up the advantages and disadvantages of this method of water management, and considers the potential role that this non‐conventional source of water could play as a strategic resource in the future. The main findings of the study are that desalination is not a panacea; rather, it should be considered in terms of technological parameters tailored to the circumstances of each geographical and socioeconomic environment.  相似文献   
129.
This article addresses the results of a structural strengthening solution for rubble stone masonry walls. The strengthening includes inserting three-dimensional steel ties across the thickness of the walls and a 30-mm layer of air-lime and cement mortar render reinforced with glass fiber mesh (textile-reinforced mortar), on both sides of the wall. The strengthening solution was found to be efficient for rehabilitating ancient rubble stone masonry walls due to the “three-dimensional” confinement, provided by the steel wires, by offsetting the low cohesive capacity of the mortar used in the walls and thus improving the mechanical resistance and delaying the collapse mechanisms. This study is part of an experimental research program carried out in Universidade Nova de Lisboa, to evaluate structural strengthening solutions for ancient rubble stone masonry buildings. To this end, three specimens of rubble stone masonry walls without strengthening (unreinforced masonry) and other three, with the mentioned strengthening solution, were subjected to compression and shear load tests. Building materials were also tested in order to characterize physical, chemical and mechanical properties.  相似文献   
130.
Long-distance commuting (LDC) is an increasingly relevant strategy of labor mobility worldwide and is therefore key to understanding the structure and dynamics of labor markets. However, little is known about the effect that LDC has on the labor market equilibrium of host territories. This paper addresses this gap for the case of Chile. While LDC is a useful strategy for improving salary and employment on a national scale, our results show a negative effect for residents in host territories (on a local scale), particularly when LDC results in commuters with similar characteristics to residents competing for the same jobs.  相似文献   
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