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121.
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   
122.
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   
123.
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   
124.
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   
125.
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   
126.
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   
127.
C.K. Brain documented two interesting patterns in the Pleistocene faunas of Swartkrans Cave, South Africa: (1) The earliest depositional units, Members 1 and 2, preserve high numbers of hominid fossils, while the numbers drop sharply in the more recent Member 3. (2) Burned bone specimens, which seem to have been altered in fires tended by hominids, appear for the first time in Member 3. It was suggested that mastery of fire provided a “shift in the balance of power”, allowing hominids to carry out activities in the cave for the first time unmolested by predators. A lack of butchered bones in Members 1 and 2 and their presence in Member 3 provided support for the hypothesis. However, we have now identified butchered bones in all three units. Further, our findings reveal a lack of variability in butchery patterns through time at Swartkrans; in all cases hominids appear to have been proficient carcass foragers. The real “shift” at Swartkrans does not appear to be one of eventual hominid dominance over carnivores, but rather one of a predominance of leopards at Swartkrans in Member 1 times to the alternating presence of leopards and hyenas in Members 2 and 3. Consistent leopard presence in Member 1 seems to have discouraged hominid activity in the vicinity of the cave. In contrast, by the time Members 2 and 3 were forming hominids may have temporarily used the cave, taking advantage of those periods of carnivore absence.  相似文献   
128.
Lapa das Boleiras rockshelter, a Paleoamerican archaeological site in Central Brazil, was intensely occupied by humans from 10,000 14C BP (11.8 cal kyr BP), until approximately 7500 14C BP (8.4 cal kyr BP). In this paper we present some interpretations about the formation processes operating on the site. One of our main conclusions is that the bulk of accumulated sediments at the site is of anthropogenic origin: they are constituted by volumetrically significant quantities of plant ash remains, what is somewhat unexpectedly in view of prevailing models about the lifestyle of Paleoamerican hunter–gatherers in South America. The evidence we discuss below is also consistent with paleoenvironmental data that suggest a dry period during the mid-Holocene in the region, probably leading to a decrease in human occupation [Araujo, A.G.M., Neves, W., Piló, L.B., Atui, J.P., 2005. Holocene dryness and human occupation in Brazil during the ‘Archaic Gap’. Quaternary Research 64, 298–307]. We surmise that both factors underpin a surprising reduction in sediment accumulation at the site during the mid-Holocene.  相似文献   
129.
Hunting and Scavenging by Early Humans: The State of the Debate   总被引:1,自引:0,他引:1  
During the last 25 years, there has been a shift towards the belief that early humans were scavengers instead of hunters. This revisionist interpretation has brought a reconciliation with the Darwinian paradigm of gradual progressive evolution that has traditionally guided (and very often, misled) an important part of anthropological thinking. However, empirical support for the scavenging hypothesis is still lacking. Recent data based on bone surface modifications from archaeological faunas suggest, in contrast, that hominids were primary agents of carcass exploitation. Meat seems to have been an important part of Plio-Pleistocene hominid diets. Passive scavenging scenarios show that this kind of opportunistic strategy cannot afford significant meat yields. Therefore, the hunting hypothesis has not yet been disproved. This makes the hunting-and-scavenging issue more controversial than before, and calls for a revision of the current interpretive frameworks and ideas about early human behavior.  相似文献   
130.
ABSTRACT

The preservation of the architectural heritage is characterized by the intervention of different technicians, who may disagree on decision-making criteria. In recent years, the H-BIM methodology has emerged to manage these buildings, although the multidisciplinary technical personnel make the decision-taking something of a challenge. In this regard, artificial intelligence may be an opportunity to establish automatic responses, thus optimizing the process. This article proposes a methodology to implement models of classification using the J48 algorithm in a H-BIM model. The case study was focused on a tiles panel from a building which belongs to the Real Alcazar of Seville. First, a model of classification was developed to estimate the degree of intervention with an adequate degree of adjustment. Then, the model was implemented in the H-BIM software by programming using GDL. This methodology automates the decision-making and reduces times of assessments, visualizing and managing the information in the H-BIM model.  相似文献   
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