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31.
Ximena S. Villagran Andrea L. Balbo Marco Madella Assumpció Vila Jordi Estevez 《Journal of archaeological science》2011
Commonly used in archaeological contexts, micromorphology did not see a parallel advance in the field of experimental archaeology. Drawing from early work conducted in the 1990’s on ethnohistoric sites in the Beagle Channel, we analyze a set of 25 thin sections taken from control features and experimental tests. The control features include animal pathways and environmental contexts (beach samples, forest litter, soils from the proximities of archaeological sites), while the experimental samples comprise anthropic structures, such as hearths, and valves of Mytilus edulis (the most important component of shell middens in the region) heated from 200 °C to 800 °C. Their micromorphological study constitutes a modern analogue to assist archaeologists studying site formation and ethnographical settings in cold climates, with particular emphasis on shell midden contexts. 相似文献
32.
This article presents a study on welded beam-to-column joints of moment-resisting steel frames. The main features of the joint specimens are summarised, in order to identify key parameters influencing the joint response as well as their low-cycle fatigue endurance. The cyclic behavior and the low-cycle fatigue strength of the connections were initially assessed by cyclic quasi-static testing, carried out at the Technical University of Milan. Analysis of the results has been carried out in order to verify the validity of a linear damage accumulation model combined with a low-cycle fatigue approach based on S-N lines concept. Moreover, a criterion to predict the type of failure and a procedure of appraising the fatigue endurance are presented and their validity proved by the results of variable amplitude tests. 相似文献
33.
Claudio Bernuzzi Arturo di Gioia Marco Simoncelli 《Journal of Earthquake Engineering》2013,17(8):1256-1282
Among the various types of industrial solutions used to store goods and products, the light duty hand loaded shelving rack (SR) typology represents a very popular solution for domestic applications, libraries and for superstores/markets open to the public. Despite the limited cost, an eventual collapse could result in significant damage of stored goods, injuries, and potentially the loss of human life, with the possible consequence of a long suspension of commercial activities. This reflects directly on the great importance of a correct design that, despite the large use of SRs, is nowadays developed with approaches characterized by inadequate levels of reliability.A research program on SRs is currently in progress in Italy, with the aim of improving the rules for both static and seismic design and this article presents a combined experimental-numerical study. Both component and pushover tests have been carried out, that are shortly summarized. Overall frame response has been simulated by means of advanced finite element software able to capture key features of the nonlinear response of slender frames with mono-symmetric cross-section members. 相似文献
34.
Marco R. Celio 《Journal of the history of the neurosciences》2013,22(2):186-190
The question as to whether an extracellular matrix exists between cells in the adult brain has been debated since the end of the last century. In the early years, zones containing neuropil and glial processes were mistakenly believed to represent this substance. But Golgi's discovery of the “perineuronal net” paved the way for future study of the true extracellular matrix. In the 1950s, application of histochemical techniques established the existence of interstitial material between nerve cells. Unfortunately the similarity between the pericellular distribution of this material and Golgi's “pericellular nets” was overlooked. The detection of an extracellular volume fraction in the central nervous system furnished further indirect proof for the existence of an extracellular matrix in the brain. However, the repeated failure of electron microscopy to reveal a substantial space between cell processes undermined the acceptance of the concept of “extracellular matrix” in the central nervous system. Nowadays this concept has, however, been firmly established. 相似文献
35.
Regional policies across Europe aim at stimulating regional development in non-core regions through fostering entrepreneurship. However, the policies applied in non-core regions and the concepts of entrepreneurship these policies are based on differ. Therefore, the goal of this review is to identify different understandings of entrepreneurship and their role for regional development processes in European non-core regions. To this end, empirical studies investigating entrepreneurship in European non-core regions from 1999 to 2011 were analysed. The results of the analysis are presented along three drivers and outcomes of entrepreneurship identified inductively from the literature: innovation, social capital and institutional change. We made out seven different types of entrepreneurship in European non-core regions. These seven types of entrepreneurship comprise particular mechanisms through which they stimulate regional development. Further research should study the interplay between these different mechanisms of regional development in non-core regions which may induce a more territorial approach to understand entrepreneurship in non-core regions across Europe. 相似文献
36.
Fragments of Roman sewn‐plank boats have been found, during rescue excavations, in the Canale Anfora, an artificial channel used by Roman ships to enter the Roman city of Aquileia. Remains were found in both 1988 and 2005 at the same site. Elements of what were probably two boats are analysed and compared to other finds of Roman sewn boats found along the coast of the Veneto and Friuli Venezia Giulia regions. They are evidence of the use of this technique, instead of the more widespread mortise‐and‐tenon system, in the quite limited area of the Northern Adriatic. These boats were used both for inland and for maritime navigation. 相似文献
37.
38.
Carlo Capra 《Journal of Modern Italian Studies》2013,18(2):218-233
This essay surveys the main reforms carried out by the Habsburg governments in Lombardy and Tuscany from the 1730s to around 1790 in the light of recent historical literature. Venturi's biographical approach to the theme is discussed in the first part of the essay, which then sets out to compare reforming activities in the two states in the fields of the administration of justice, ecclesiastical policy, and public finance. The drive towards centralization and uniformity is identified as the main aspect of the Milan reform movement, to the liberal and humanitarian tendencies of Peter Leopold's government in Tuscany. 相似文献
39.
Marco Valente 《Journal of Earthquake Engineering》2018,22(8):2-34
ABSTRACTHistorical masonry structures are often located in earthquake-prone regions and the majority of them are considered to be seismically vulnerable and unsafe. Historical masonry towers are slender structures that exhibit unique architectural features and may present many inadequacies in terms of seismic performance. The seismic protection of such typologies of structures and the design of effective retrofitting interventions require a deep understanding of their behavior under horizontal loads. This paper presents the results of the seismic performance evaluation of historical masonry towers located in Northern Italy. A large set of case studies is considered, comprising a significant number of towers with high slenderness and marked inclination. First, a preliminary assessment of the dynamic behavior of the different towers is carried out through eigenfrequency analyses. Then, non-linear dynamic simulations are performed using a real accelerogram with different peak ground accelerations. A damage plasticity material model, exhibiting softening in both tension and compression, is adopted for masonry. The huge amount of results obtained from the non-linear dynamic simulations allows a comparative analysis of the towers to be performed in order to assess their seismic vulnerability and to show the dependence of their structural behavior on some geometrical characteristics, such as slenderness, inclination, and presence of openings and belfry. The evaluation of different response parameters and the examination of tensile damage distributions show the high vulnerability of historical masonry towers under horizontal loads, mainly in the presence of marked inclination and high slenderness. Some general trends of the seismic behavior of the towers are deduced as a function of the main typological features. 相似文献
40.
Rossella Duches Marco Peresani Paolo Pasetti 《Archaeological and Anthropological Sciences》2018,10(7):1617-1643
It is generally recognized that the function and modality of hafting are the main factors influencing mental templates, and consequently, stone tool standardization. But what role do technical knowledge and traditions play? In this study, we investigate the interaction between mental templates and technological choices in the manufacture of Late Epigravettian projectile implements. The examined specimens come from different dwelling phases of the Dalmeri rock shelter (Italian Alps). Technological analyses suggest that lithic production systems gradually simplified their structure over time, implying a shift in technical investment from shaping on the core to a subsequent shaping on the derived flake blank. However, correlations between the dimensions and morphological features among the armatures from the different units suggest that mental templates remained unchanged throughout the Alleröd. Experimentation attests to the frequent combined application of different retouching techniques. Further, the variability in their arrangement denotes the absence of strict rules and the Epigravettian capability to recognize the most situationally suitable method. In the Dalmeri rock shelter, the standardization of lithic projectile implements is therefore a result of flexibility in retouching, framed in a production system characterized by a progressive simplification. A such rapidly produced and responsive technology must have been encouraged by Late Glacial climatic and environmental changes and the occupation of alpine territories previously inaccessible. Thus, the flexibility of technical behaviors turns out to be a key element in the transformation of Late Epigravettian societies during this period, enabling them to adapt and evolve in response to environmental, social, and economic changes. 相似文献