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Bruno Calderoni Giuseppe Cecere Emilia Angela Cordasco Luigi Guerriero Pietro Lenza Gaetano Manfredi 《Journal of Cultural Heritage》2010,11(2):163-171
The knowledge of the morphological and mechanical properties of masonry walls is very important for the refurbishment of ancient buildings, particularly when the requirements of both structural safety and historical preservation must be fulfilled. The masonry is not of homogenous material: its mechanical properties depend on stones, mortar, and texture which are very variable due to their dependence on the historical periods and the geographical area of the erection. For this reason, a deep knowledge of masonries built in different sites and historical periods is essential in order to evaluate both the capacities of bearing vertical load and the seismic vulnerability of the masonry structure. Three fundamental typologies of tuff masonry have been defined: they are the characteristics of different historical periods from the XVI to the XX century. The models are in full-scale in order to reproduce the three defined chronotypes. Original tuff stones quarried in the corresponding historical period, mortars similar to the original ones, reproduced according to ancient documents and original constructive techniques have been used for the construction of the specimens. Compression tests performed in displacement control have been carried out on the masonry models in order to determine the maximum resistance of the material and the corresponding strain, the ultimate strain and corresponding residual strength. In this paper, the procedure used for making the specimens and for experimentally evaluating the mechanical properties of post-medieval Neapolitan yellow tuff masonry are illustrated and the obtained results, even in terms of plastic capacity of these kinds of masonry, are reported. 相似文献
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Gradual refinement for application-specific MPSoC design from Simulink model to RTL implementation 总被引：1，自引：0，他引：1
Kai Huang Xiao-lang Yan Sang-il Han Soo-ik Chae Ahmed A. Jerraya Katalin Popovici Xavier Guerin Lisane Brisolara Luigi Carro 《浙江大学学报(A卷英文版)》2009,10(2):151-164
The application-specific multiprocessor system-on-chip （MPSoC） architecture is becoming an attractive solution to deal with increasingly complex embedded applications, which require both high performance and flexible programmability. As an effective method for MPSoC development, we present a gradual refinement flow starting from a high-level Simulink model to a synthesizable and executable hardware and software specification. The proposed methodology consists of five different abstract levels： Simulink combined algorithm and architecture model （CAAM）, virtual architecture （VA）, transactional accurate architecture （TA）, virtual prototype （VP） and field-programmable gate array （FPGA） emulation. Experimental results of Motion-JPEG and H.264 show that the proposed gradual refinement flow can generate various MPSoC architectures from an original Simulink model, allowing processor, communication and tasks design space exploration. 相似文献
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Governments around the world are investing a great amount of resources on the development of an information society. These investments are particularly important as an attempt to close digital divides among countries and regions within countries. However, there is no clear evidence that suggests that current Information and Communication Technology (ICT) policies are helping align investments with the actual needs of the local contexts. Based on data about the allocation of 2014–2020 EU Funds, this paper analyzes the relationship between local needs and investment decisions aiming at bridging territorial digital divides. The results identify four different regional strategies developed around four policy goals: broadband, digital inclusion, digital government services, and the use of ICTs in enterprises. The results also show that unlike the past 2007–13 period, the allocations to these goals appear to be consistent with the ICT local context, i.e. funding for a given goal is higher in the regions that need it the most. Therefore, our main recommendation for the European Commission and Member States is to keep existing requirements for developing evidence-informed “Digital Growth” strategies for the next 2021–27 period. We also suggest to strengthen existing support tools for regional governments. 相似文献
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This article analyzes the impact of a computer simulation (business game) on the users’ perceived learning. The theoretical model developed in this paper is derived from collaborative learning and human–computer interaction assumptions. The hypotheses relating to group dynamics and the user–computer interface design with the users’ perceived learning are tested using the business game “FirmReality” on a sample of 173 respondents. Multiple regression and qualitative results show that, in a computer-based simulation context, perceived learning is influenced more by human–computer interaction factors than by group dynamics. Furthermore, results point out a negative effect of interaction with the instructor on individual perceived learning. These results support the possibility to automate the interaction between teacher and students. 相似文献
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Maria Chiara Gallotta Gian Pietro Emerenziani Sara Iazzoni Luigi Iasevoli Laura Guidetti 《Journal of sports sciences》2017,35(15):1547-1555
Aim of this study was to evaluate the effectiveness of two different 5-month physical education (PE) interventions conducted by a specialist PE teacher on primary school children’s skill- and health-related outcomes. About 230 children were randomly assigned to one of three intervention groups: experimental_1 group, experimental_2 group or control group (school curriculum given by the generalist teacher). Pre- and post-intervention tests assessed pupils’ fitness (pacer, curl-up, push-up, trunk lift, sit and reach tests) and gross motor coordination (shifting platforms, balance beam, jumping laterally, hopping on one leg over an obstacle tests). Both experimental groups significantly improved some fitness and coordinative tests after the intervention period when compared with control group. However, no differential changes on coordinative development were observed between the 2 experimental groups. Results of this study demonstrated that children benefitted from a well-structured PE intervention conducted and supervised by a specialist PE teacher improving their motor skills and fitness. 相似文献
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Giacomo Cipriani Antonella Salvini Luigi Dei Azzurra Macherelli Francesco Saverio Cecchi Carlo Giannelli 《Journal of Cultural Heritage》2009,10(3):388-395
The cross-linking processes of three drying oils (poppy, linseed, walnut), a class of organic compounds very important in the field of artworks, were studied by means of 1H-NMR spectroscopy, following the change of the protons signals when oils are heated at 60 °C in the presence of air or nitrogen gas. This preliminary information is particularly important to identify the presence of drying oils within a solid painting film. We demonstrated that it was possible to study these films by swollen-state NMR, an innovative spectroscopy method that can directly analyze very small semisolid samples instead of solutions. The main advantages of this method are the short time of analysis, the possibility to analyze samples without any preliminary treatment, and the small quantity of the sample required. Therefore, swollen-state NMR technique was used to characterize three real painting films: in this way, we succeeded in recognizing in real paintings specimens the presence of drying oils employed as binders, avoiding any interferences due to other organic compounds acting as binding agents, like waxes or egg-yolk media. 相似文献
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Emiliano Carretti Marco Milano Luigi Dei Piero Baglioni 《Journal of Cultural Heritage》2009,10(4):501-508
The present work was one of the first attempts to analyze the conservation status of two ferrotypes, ancient photographic plates realized on a support made of iron. The photographic material was constituted of collodion as binder for the photosensitive silver halides grains. The two ferrotypes studied belonged to a private collection of a family from Durham, UK, and were made at the end of the 19th century. The analytical techniques used for the morphological and physicochemical characterization were noninvasive. The surface morphology was studied by means of optical microscopy (OM) and environmental scanning electron microscopy (ESEM) coupled with an energy dispersive X-rays (EDX) system for the elemental analysis. These techniques, together with microreflectance Fourier transform infrared spectroscopy (μ-FTIR) and contact angle, allowed to obtain information on both the chemical – elemental – composition of the materials constituting the ferrotypes, and the conservation status of these photographic plates. The study showed that the physicochemical diagnostics allowed to characterize the two ferrotypes that, despite their similar age and provenance, showed different conservation status, surface properties, and elemental composition. 相似文献