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11.
This paper analyses the role of national research funds in promoting scientific production in emerging economies. The study focuses on the impact of the Chilean National Science and Technology Research Fund (FONDECYT). The analysis uses data drawn from international sources of bibliometric information combined with the administrative records of the program's executing unit. To measure the program's impact, we implement a regression discontinuity (RD) design on principal researchers who applied for funding between 1988 and 1997 considering as outcomes both quantity (publications up to 2002) and quality (citations up to 2005) of their scientific production. Our results show significant and positive impact in terms of publications, but no impact in terms of quality of scientific production in the proximity of the program's threshold ranking.  相似文献   
12.
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   
13.
This paper presents conditions to assure the exponential stability in probability for autonomous switching linear systems. The switching signal acting on the autonomous system produces intervals that follow independent, identically distributed stochastic processes—the stability then follows by verifying simple-to-check linear matrix inequalities.  相似文献   
14.
This study employs digital methods in conjunction with traditional content and discourse analyses to explore how the US President Donald Trump conducts diplomacy on Twitter and how, if at all, diplomatic entities around the world engage in diplomatic exchanges with him. The results confirm speculations that Trump’s diplomatic communication on Twitter disrupts traditional codes of diplomatic language but show little evidence that new codes of diplomatic interactions on social media are being constructed, given that other diplomatic entities around the world mostly remain within the confines of traditional notions of diplomacy in (not) communicating with Trump on Twitter.  相似文献   
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16.
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   
17.
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   
18.
Some of the most important challenges for engineering schools at the beginning of the 21st century are summarised as well as the role of ERASMUS Thematic Networks (TN) in this scenario.

Though focus is mainly given to the European environment, the changes which are interesting Engineering Education appear to involve also the non-European sphere and therefore, this set of papers on the main outcomes of E4 Thematic Network (2000–2004) has been conceived, not only as an useful instrument of dissemination, but also an open window on Europe.

In this introductory paper key characteristics of successful TNs are outlined, as resulting from the experience of TN E4, Enhancing Engineering Education in Europe, which has terminated its life end of September 2004. The new TN project, denominated TREE, for Teaching and Research in Engineering in Europe, is briefly presented.

On the other hand, in the following 5 sections some of the main activities developed within E4 are presented touching topics related to accreditation, quality assurance, students involvement in Engineering Education, ICT and new learning methods and curriculum development.  相似文献   

19.
Teacher burnout is a growing phenomenon that may dramatically reduce the quality of life of both teachers and students. Many studies have conceptualized teaching as a high-contact profession and, focusing on the emotional exhaustion dimension of burnout, they have highlighted the relation with students as a key dimension of teachers’ stress. This paper presents an original instrument (TSS-Sr) to measure teachers’ stress related to the interaction with their pupils. It provides the psychometric characteristic of this scale. Results support a model of measurement of teacher social stress based on four dimensions: verbal aggression, dislike students, awkward reactions, demanding requests. Implications about the use and the applications of this instrument are discussed.  相似文献   
20.
This paper proposes a quantitative analysis of social distance between Open Science and Proprietary Technology. A few general properties of social networks within both realms are discussed, as they emerge from the new economics of science and recent applied work on “small worlds”. A new data-set on patent inventors is explored, in order to show that social networks within Proprietary Technology are much more fragmented than Open Science ones, except for science-based technologies. Two propositions are then put forward on the “open” behaviour expected from academic inventors, namely university scientists getting involved in Proprietary Technology networks by signing patents. Both propositions are confirmed by data, which show academic inventors to be more central and better connected than non-academic ones. The database and methodology produced for this paper are suggested to be relevant for the more general debate on the role of geographical and cognitive distance in university-industry technology transfer.  相似文献   
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