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71.
The aim of this paper is to analyse some relevant aspects on productivity distribution in the European Union at regional level. Firstly, the paper examines its external shape and intra-distribution dynamics. Subsequently, an analysis of the factors that might be behind the productivity distribution and its dynamics is carried out. The results, represented by means of a relatively new visualization tool, highlight the role played by factors such as geographical location, compensation per employee and investment per employee in explaining this issue.  相似文献   
72.
Recent research in Paleolithic archeology has stressed the importance of temporal issues in assemblage interpretation. Archeological assemblages are temporal constructs, formed by the addition of an unknown number of depositional events. This temporal dimension is also evident at the artifactual level, since single artifacts may undergo different events of modification and/or uses over time. The recycling of previously discarded blanks for tool production is one of the best examples of the temporal nature of artifacts. The aim of this paper is to evaluate the importance of recycling in a Late Upper Paleolithic site, examining a type of artifact – burned tools – that has up to now been little used to approach this issue. Our results suggest that recycling was probably a significant component of Upper Paleolithic provisioning behavior, with important implications in site formation processes and the typological variability of assemblages. The expedient or curated character of recycling is also discussed.  相似文献   
73.
In this article we calculate an indicator of social and economic development using the DP2 distance method to measure the disparities in Objective-1 regions of southern European countries for 2006. In addition to per capita income, socio-economic components such as health, education, employment, scientific and technological development and infrastructure provision have been incorporated into the index. We examine the issue of whether the Europe Union regions included in the Convergence Objective achieved a lower level of development than the regions no longer covered in this objective for the 2007–2013 programming period by establishing a territorial classification based on the value yielded by the variables of the DP2. Our indicator constitutes a novel contribution insofar as it was constructed using a large number of variables. In essence, we show that not all the regions of the Convergence Objective presented a lower level of economic and social development than those that lost this consideration between 2007 and 2013 and the opposite.  相似文献   
74.
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   
75.
It is generally accepted that abstract and iconographic representations are reflections of symbolic material culture. Here we describe a fragmented ocherous pebble bearing a sequence of sub-parallel linear incisions. These were produced by a lithic point and may represent one of the oldest instances of a deliberate engraving. The object was recovered from Middle Stone Age II levels of Klasies River Cave 1, South Africa, and is dated to between 100,000 and 85,000 years ago. Microscopic analysis reveals that the surface of the object was ground until smooth before being engraved with a sequence of sub-parallel lines made by single and multiple strokes. X-ray fluorescence and colorimetric analysis of the object and a sample of twelve additional ochre pieces from the same level reveals that the brown colour and Manganese-rich composition renders the engraved piece distinct. This suggests that a particular type of raw material may have been selected for engraving purposes. Although the purpose of marking this object remains uncertain, its detailed analysis adds relevant information to previously published occurrences of Middle Stone Age engraved objects and contributes to clarify their distribution through time and space.  相似文献   
76.
This article explores the relevance of acoustics as a factor for in the production and active use of Levantine rock art in Spain. The renowned rock art area of La Valltorta Gorge serves as a case study. Two experiments are described; the first assessed whether the sites with the most painted motifs had better acoustics than those with fewer motifs. The second tested which areas in La Valltorta Gorge had better acoustics and whether there was a difference between the acoustics of the decorated area and the contiguous sectors of the Gorge where no paintings have been found. In both experiments different sounds and pitches were used. The results suggest a strong relationship between the painted areas and the sonority of the place, with the major sites generally having provided the best results, with the exception of the sonority when facing the rock art panels. It is suggested that La Valltorta Gorge was chosen to be decorated with a view to increasing the perceptual impact of the rituals that may have been held at rock art sites due to the amplification caused by the echoing and resonance.  相似文献   
77.
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   
78.
79.
We present the first analysis of the influence of climate change on carbon and oxygen isotope fractionation factors for two saccharides (glucose and α-cellulose) of pine wood. The conifers grew in the Niepo?omice Forest in Poland and the annual rings covered a time span from 1935 to 2000 AD. Glucose samples from acid hydrolysis of α-cellulose were extracted from annual tree rings. The carbon and oxygen isotope fractionation factors between glucose and α-cellulose were not stable over time. The mean value for the carbon isotope fractionation factors between glucose and α-cellulose was greater than unity. The mean value for the oxygen isotope fractionation factors between glucose and α-cellulose was lower than unity. We established, with respect to climate change, the significance of the interannual and intraannual variation in the carbon and oxygen isotope fractionation factors between both saccharides. We used moving interval correlation results for May of the previous year through September of the current year using a base length of 48 years. The relationship with summer temperature is the main climate signal in the carbon isotope fractionation factor between glucose and α-cellulose. The relationship with autumn sunshine is the main climate signal in the oxygen isotope fractionation factor between glucose and α-cellulose for the tree ring chronology.  相似文献   
80.
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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