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1.
One set of samples from wall paintings of the Xth Regio of Italy containing green colours was analysed exploiting different spectroscopic techniques, aiming to identify the pigments used. The possibility to distinguish between glauconite and celadonite, the most common green pigments used in such paintings, was of particular interest. Samples of celadonite from Monte Baldo and glauconite from Belgium were considered as standard materials for comparison. The results obtained using FTIR, EDS, AAS, Colorimetry, Raman and EPR spectroscopies were compared for the identification of the green pigments.  相似文献   
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Academic inventors as brokers   总被引:4,自引:0,他引:4  
Academic inventors are university scientists who appear as designated inventors of patents owned either by business companies, academic institutions or individuals. We analyse their relationships with co-inventors, who may be either academic colleagues, students, or, very often, industrial researchers. Gould and Fernandez's (1989) taxonomy of ‘brokerage’ roles is adjusted to patent data, and complemented with information drawn from both academic inventors’ publications and replies to a short questionnaire. Only very few academic inventors are found to hold brokerage positions. Such inventors have a large number of patents, a strong publication record and a higher-than-average share of patents held by companies, rather than universities. Relationships of academic inventors with co-inventors from industry are weaker and less likely to be maintained than those with co-inventors from academia. Academic inventors in gatekeeping positions (between university and industry) maintain the strongest ties with all types of co-inventors.  相似文献   
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Research assessment exercises have now become common evaluation tools in a number of countries. These exercises have the goal of guiding merit-based public funds allocation, stimulating improvement of research productivity through competition and assessing the impact of adopted research support policies. One case in point is Italy's most recent research assessment effort, VQR 2011–2014 (Research Quality Evaluation), which, in addition to research institutions, also evaluated university departments, and individuals in some cases (i.e., recently hired research staff and members of PhD committees). However, the way an institution's score was divided, according to VQR rules, between its constituent departments or its staff members does not enjoy many desirable properties well known from coalitional game theory (e.g., budget balance, fairness, marginality). We propose, instead, an alternative score division rule that is based on the notion of Shapley value, a well known solution concept in coalitional game theory, which enjoys the desirable properties mentioned above. For a significant test case (namely, Sapienza University of Rome, the largest university in Italy), we present a detailed comparison of the scores obtained, for substructures and individuals, by applying the official VQR rules, with those resulting from Shapley value computations. We show that there are significant differences in the resulting scores, making room for improvements in the allocation rules used in research assessment exercises.  相似文献   
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This explorative case study aims at shedding light on the utilization of a specific Intranet-based knowledge-sharing platform, the ShareNet. This system is part of a €1bn investment campaign to transform Siemens into an e-driven company, and it is an important example of system enabling knowledge sharing between local subsidiaries within large multinationals. By investigating how such company-wide system is structured and employed a theoretical model and three propositions about IT contribution to intra-firm knowledge sharing are formulated. Findings lead to the conclusion that, on one hand, IT systems represent an efficient mechanism for knowledge duplication through imitation between units with similar capabilities and, on the other, as a trigger for direct interaction resulting in knowledge development through joint problem solving between units having complementary capabilities.  相似文献   
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This work reports mainly the results of an X-ray Absorption Spectroscopy (XAS) study carried out on coloured glass tesserae from the palaeo-Christian mosaic which decorated the votive chapel of St. Prosdocimus (Padova) until its replacement with the current frescoes of Renaissance age, and which is one of the only two known mosaics in the Veneto region (Italy). The study aims at clarifying how the different local structure, oxidation state and quantity of copper influenced colour. Analysis of high-resolution Cu-K edge X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) spectra showed that copper is present as cuprite (Cu2O) in orange samples and as metallic copper in red and brown ones. These phases are responsible for both the colour and opacity of the samples. In addition, Cu1+ ions linked to the oxygen atoms of the glass framework were identified in ratios of about 60% and 30% of total copper in orange and red/brown samples, respectively. In blue and green samples, copper is dispersed in the glass matrix as a mixture of Cu1+ and Cu2+ ions, and no crystalline phases are visible. In this context, the Cu1+ and Cu2+ contents in glass were also quantified thanks to suitable standards, demonstrating that, when Cu2+ is the main chromophorous ion, colour intensity is directly correlated to its content in the glass. In particular, in green and blue samples, coloured by copper, Cu2+ content varies from 26% to 56% of total copper, and the higher contents of Cu2+ are shown by more intensely coloured samples. It should be stressed here that the green colour of the analysed tesserae is given by the physical interaction of blue colour, due to Cu2+ ions, and yellow colour, due to Pb antimonates used as opacifiers.  相似文献   
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This article compares four European information and communication technologies (ICT) development projects spawned by national and EU initiatives to create the “European information society.” These projects, which sought to support learning and better use of ICT, were all the result of opportunities opened up by political initiatives. The analysis indicates that the main problems that afflict these projects stem from varied expectations and interests of the major actors. These problems can be mitigated considerably if a feeling of ownership is generated among the participants. This sense of belonging, however, is difficult to foster in a “top-down” project. Hence there is a need for a better balance between the “top-down” and “bottom-up” influences in the development of such projects.  相似文献   
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Theorems are stated and proved that provide necessary and sufficient conditions for practical stability of discrete-time systems.The first part of the paper deals with stability and instability with respect to time-varying sets, whereas the second part is devoted to the study of final and semi-final stability. The conditions obtained, which take the form of existence of discrete Lyapunov-like functions, generalize previous results.  相似文献   
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