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To most English readers the Lower Paleolithic of the Iberian peninsula is known mainly through a few sites such as Torralba and Ambrona, whose age and behavioral significance remain controversial. In fact, the archaeological data base for this period and region is much larger and more varied than is generally appreciated and includes primary-context sites such as Aridos that have provided unique combinations of evidence on hominid exploitation of elephant carcasses. This paper is both a comprehensive synthesis of our current knowledge and a first attempt to see patterns in the data. Every major occurrence is presented in its regional and geochronological framework; each is critically assessed for data quality and behavioral significance. Major issues addressed in this paper include the working out of regional sequences and intersite correlation, the age and significance of the oldest occurrences, the density and preferred areas of settlement within each region, temporal variation within the Acheulean, and the strength and weaknesses of the data and of our approaches to it.M.S. is responsible for the research and form of this paper; P.V. is responsible for translating, editing, and revising certain sections in consultation with the senior author.  相似文献   
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ABSTRACT. During the last thirty years there has been much research effort in regional science devoted to modeling interactions over geographic space. Theoretical approaches for studying these phenomena have been modified considerably. This paper suggests a new modeling approach, based upon a general nested sigmoid neural network model. Its feasibility is illustrated in the context of modeling interregional telecommunication traffic in Austria, and its performance is evaluated in comparison with the classical regression approach of the gravity type. The application of this neural network approach may be viewed as a three-stage process. The first stage refers to the identification of an appropriate network from the family of two-layered feedforward networks with 3 input nodes, one layer of (sigmoidal) intermediate nodes and one (sigmoidal) output node (logistic activation function). There is no general procedure to address this problem. We solved this issue experimentally. The input-output dimensions have been chosen in order to make the comparison with the gravity model as close as possible. The second stage involves the estimation of the network parameters of the selected neural network model. This is performed via the adaptive setting of the network parameters (training, estimation) by means of the application of a least mean squared error goal and the error back propagating technique, a recursive learning procedure using a gradient search to minimize the error goal. Particular emphasis is laid on the sensitivity of the network performance to the choice of the initial network parameters, as well as on the problem of overfitting. The final stage of applying the neural network approach refers to the testing of the interregional teletraffic flows predicted. Prediction quality is analyzed by means of two performance measures, average relative variance and the coefficient of determination, as well as by the use of residual analysis. The analysis shows that the neural network model approach outperforms the classical regression approach to modeling telecommunication traffic in Austria.  相似文献   
44.
The managers of a growing wall of money are continuously searching for investment opportunities. The financialization literature describes how this mobile capital puts pressure on commodities, debt, public services and economic activities to transform into investable, tradable, financial products. Regarding real estate, these investigations show how opaque, local, non-standardized goods, highly depending on both local legislation and developments, have been transformed into liquid, globally traded financial assets. By analysing the real estate investment strategies of Dutch institutional investors since the 1980s, this paper shows how a quantitative framework increasingly provides the basis for institutional investors’ real estate investment strategies. Direct ownership of properties has been exchanged into shares of properties, that is, fictitious capital, creating an impetus for ‘objectified numbers’ to measure the performance of these indirect investments. As knowledge about real estate has been outsourced, Dutch institutional investors now perceive real estate increasingly as ‘just another asset class’, thereby increasing leverage and volatility. This paper not only shows how finance ‘financialized’ itself by adopting a quantitative investment perspective, but it also offers an empirical account on how investment properties are transformed into financial assets that put pressure on state agencies to mobilize urban planning to deliver more of such assets.  相似文献   
45.
ABSTRACT

The aim of this article is to analyze two Spanish documentary films that reflect on the 2008 financial crisis in Spain, Mercado de futuros (Mercedes Álvarez, 2011) and No estamos solos (Pere Joan Ventura, 2015). These movies could be marked as political for their choice of a collective protagonist and for dealing with the issues of inequality with the purpose of appealing to mobilization and resistance to the neoliberal Western agenda that have provoked social cutbacks after the 2008 crisis. Mercedes Álvarez and Pere Joan Ventura follow the tradition of political documentaries traced by filmmakers such as Dziga Vertov, Joris Ivens, Pere Portabella, and Basilio Martín Patino and open the debate on how people can contribute to searching for renewal policies in times of crisis.  相似文献   
46.
In the scope of European Cooperation in Science and Technology–Wood Science for Conservation of Cultural Heritage (COST IE0601–WoodCultHer) (available at http://www.woodculther.org) it was agreed to produce Guidelines for the Assessment of Historic Timber Structures, covering the principles and possible approaches for the safety assessment of old timber structures of historical relevance that could be used as the basis for possible European Standards, as discussed with CEN/TC346 (Conservation of Cultural Heritage).

This approach was targeted at all those concerned with the conservation of heritage buildings. These guidelines should also help decision-making regarding the need for immediate safety measures. The aim is to guarantee that inspection and assessment measures provide the necessary data for historical analysis, structural safety assessment, and planning of intervention works, while having minimal impact on the building fabric (the original materials, structural systems, and techniques).This article provides information on the criteria to be used in the assessment of load-bearing timber structures in heritage buildings. It covers the preliminary assessment (desk survey, preliminary visual survey, measured survey, structural analysis, and preliminary report), as well as the detailed survey of timbers (with a special emphasis on visual strength grading on site) and carpentry joints. The subsequent diagnostic report and the detailed design of repairs are outside its scope.  相似文献   

47.
This paper focuses on the effects of social capital on industrial clusters. Close networks with strong ties provide benefits for the companies involved in terms of knowledge flow; however, they can also have some negative effects such as knowledge redundancy and obsolescence. We propose an explanatory model to study factors and mediators affecting the redundancy of transmitted knowledge. The model has been applied to a sample of 152 companies in two Spanish industrial clusters. Findings suggest that although strength of ties was associated with redundancy, structural dispersion and local institutions have a negative effect on knowledge redundancy. The findings have a number of relevant implications for individual firms and their policies.  相似文献   
48.
The focus in this article is on knowledge spillovers between high-technology firms in Europe, as captured by patent citations. The European coverage is given by patent applications at the European Patent Office that are assigned to high-technology firms located in the EU-25 member states (except Cyprus and Malta), the two accession countries Bulgaria and Romania, and Norway and Switzerland. By following the paper trail left by citations between these high-technology patents we adopt a Poisson spatial interaction modeling perspective to identify and measure spatial separation effects to interregional knowledge spillovers. In doing so we control for technological proximity between the regions, as geographical distance could be just proxying for technological proximity. The study produces prima facie evidence that geography matters. First, geographical distance has a significant impact on knowledge spillovers, and this effect is substantial. Second, national border effects are important and dominate geographical distance effects. Knowledge flows within European countries more easily than across. Not only geography, but also technological proximity matters. Interregional knowledge flows are industry specific and occur most often between regions located close to each other in technological space.  相似文献   
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In most instances, knowledge is passed on through the medium of language. The author tries to demonstrate to what extent the Latin present in early medieval Latin medical treatises failed to fulfill its role as an efficient medium of communication, which factors may account for this failure and how scholars in the middle ages strove to restore sense in texts in various stages of corruption, an attempt that was bound to be unsuccessful in many cases owing to a lack of reliable dictionaries.  相似文献   
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