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21.
The detection of buried earthen structures by using remote sensing techniques is still an open issue and a strategic challenge as crucial as it is complex. It is crucial because earthen archaeological remains are widely present thoughtout the world (in South America, Asia, Africa) and it is complex due to the subtle physical contrast between earthen remains and the surrounding subsoil.  相似文献   
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The aim of this work is the physical and mineralogical-petrographic characterization of the mortars from the Baths with Heliocaminus, a special and unique architectural building in the complex of the Hadrian’s Villa in Tivoli. Thirty samples were investigated for composition and physical properties (density, porosity, water absorption, mechanical strength, particle size distribution of aggregate, etc.), representative of eight mortar groups: cubilia bedding mortar, brick bedding mortars, floor-coating and wall-coating bedding mortars, floor (rudus) and wall conglomerates (trullisatio), vault concretes, and lime plasters (arriccio). Physical parameters, together with the microscopic analysis and binder/aggregate ratio determined in three ways using image analysis (on thin sections and on specimens) and weight-data from dissolution of binder, have shown an interesting relationship between the physical-compositional characteristics and the function of mortars within the structure of the Heliocaminus baths. To identify the minerals and the reactant phases between binder and aggregate, as well as the hydraulic degree, selected samples were analyzed with x-ray powder diffraction, thermogravimetry, and differential scanning calorimetry techniques. The obtained results provide a close relation between pozzolanic characteristics and physical-mechanical properties of the mortars (i.e., punching strength index).  相似文献   
24.
Typical of the 1990s, the global cities phenomenon preceded the past decade’s massive spread of smart cities. Yet the question of how the two phenomena currently coincide remains to be considered, as well as an analysis based on viewing smart cities as global cities. An analysis related to the European scenario is developed in this article, aimed at giving a response to the previous considerations. An index is also proposed; concerning the global character of the cities, it considers the ability of the cities to attract Foreign Direct Investments (FDI). Results of the proposed analysis show that in Europe four main scenarios exist. Two regarding positive and negative correlations between the diffusion of global and smart cities, and another two scenarios demonstrate cases in which the two features are not correlated. The first two cases are respectively related to smart cities that are also global cities. The last two cases deal with the presence of different drivers that are not related to smart urban plans, which could, however, drive the attraction of FDI or which could also promote smart actions without the thrust of FDI. Correlation and regression analyses complement the work.  相似文献   
25.
The possibility of determining the human or animal origin of bones from the lattice parameters of their inorganic bioapatite phase, when subjected to a high temperature treatment using the powder X-ray diffraction (XRD) technique, has been explored on a wide number of specimens. Forty-two animal bones were treated in a furnace at 1100 °C for 36 min and compared to 53 cremated human bones from a range of ancient necropolises. The X-ray diffraction patterns of bioapatite were simulated using both monoclinic P21/b and hexagonal P63/m structures to verify any occurrence of phase transformation and any difference in the lattice parameters due to the model. It was determined that the differences between the a-axis and c-axis of the monoclinic and hexagonal lattice were unimportant. Some outlying values were revealed to be caused by the presence of chlorine ions diffused into the apatite structure increasing its average unit cell values. Nevertheless, our results clearly show that in terms of lattice parameters the variability of human specimens are completely overlapped by the non-human variability making the use of XRD in order to distinguish animal from human bones questionable.  相似文献   
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This article presents the results of an exhaustive parametric analysis which compares the performances offered by various systems (which lead to both classical and non classical damping matrices) of added viscous dampers in shear-type structures. The aim of the research work here presented is the identification of the system of added viscous dampers which maximizes the dissipative properties under an equal “total size” constraint. The choice of the systems of added viscous dampers considered in the comparison is carried out both using a numerical approach (based upon the use of genetic algorithms) and a physically based approach (based upon the properties of classically damped systems). The comparison is carried out through the numerical evaluation of the dynamic response of representative shear-type structures to both stochastic and recorded earthquake inputs. The results obtained using both approaches indicate that a damping system based upon the mass proportional damping component of the Rayleigh viscous damping matrix (referred to as MPD system) is capable of optimizing simultaneously a number of different performance indexes, providing the best “overall” damping performances. The MPD system is characterised by viscous dampers (a) which connect each floor to a fixed point and (b) which are sized proportionally to the corresponding floor mass.  相似文献   
27.
The Palaeolithic sequence of Grotta Paglicci (Gargano promontory, Apulia, Southern Italy) is one of the most important in the Mediterranean area: It comprises the whole Upper Palaeolithic cultural sequence known for the region, as well as Early Middle Palaeolithic and Lower Palaeolithic levels. These earlier phases are best represented in a collapsed room located outside the present-day cave (the so called “external rock shelter”). In this area, a new excavation, started in 2004, brought to light Middle Palaeolithic animal remains associated with evidence of spotted hyaena (SU 64 and 53). The spatial distribution analysis of remains from SU 53 revealed the presence of a bone accumulation area and a wider dispersal of hyaena coprolites. Three main ungulate species (aurochs, fallow deer and red deer) as well as carnivores (spotted hyaena, wolf, fox, wild cat and lynx) and lagomorphs have been identified. The majority of aurochs remains are located in the main accumulation; among these specimens, a complete metatarsal connected with three tarsal bones has been found; a talus and a complete tibia, probably belonging to the same limb, have also been identified. The multidisciplinary study carried out in this paper highlights a specific bone accumulation and scattering pattern in a spotted hyaena (Crocuta crocuta) den. In addition, taphonomy of lagomorph remains indicates the presence of other depositional agents.  相似文献   
28.
ABSTRACT

The unreinforced masonry (URM) buildings designed to be conforming with the Italian building code, as illustrated in the companion paper, were analyzed by performing time-history analyses on models realized using an equivalent frame approach and by adopting two different constitutive laws. Both the effect of record-to-record variability and of epistemic and aleatory uncertainties in modelling were explored. The achieved results constitute the basis for the evaluation of the risk level implicit in Italian code-conforming buildings. Two main performance conditions are considered, namely usability-preventing damage and global collapse limit states.  相似文献   
29.
Viscous dampers have widely proved their effectiveness in mitigating the effects of the seismic action upon building structures. In view of the large impact that use of such dissipative devices is already having and would most likely have soon in earthquake engineering applications, this article presents a practical procedure for the seismic design of building structures equipped with viscous dampers, which aims at providing practical tools for an easy identification of the mechanical characteristics of the manufactured viscous dampers which allow to achieve target levels of performances. Selected numerical applications are developed with reference to simple, but yet relevant, cases.  相似文献   
30.
This article describes tests investigating a feasible source of passive damping for post-tensioned glue-laminated (glulam) timber structures. This innovative structural system adapts precast concrete PRESSS technology [Priestley et al., 1999] to engineered wood products combining the use of post-tensioned tendons with large timber members. Current testing is aimed at further improvement of the system through additional energy dissipation. Testing has favorably compared glue-laminated timber (not previously implemented in this way) with laminated veneer lumber (LVL) used in New Zealand. After initial benchmark testing with post-tensioning only, a simple, minimally invasive and replaceable type of hysteretic damper was added.  相似文献   
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