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1.
Measuring knowledge transfer between fields of science   总被引:4,自引:2,他引:2  
In this paper we report on the results of an exploratory study of knowledge exchange between disciplines and subfields of science, based on bibliometric methods. The goal of this analysis is twofold. Firstly, we consider knowledge exchange between disciplines at a global level, by analysing cross-disciplinary citations in journal articles, based on the world publication output in 1999. Among others a central position of the Basic Life Sciences within the Life Sciences and of Physics within the Exact Sciences is shown. Limitations of analyses of interdisciplinary impact at the journal level are discussed. A second topic is a discussion of measures which may be used to quantify the rate of knowledge transfer between fields and the importance of work in a given field or for other disciplines. Two measures are applied, which appear to be proper indicators of impact of research on other fields. These indicators of interdisciplinary impact may be applied at other institutional levels as well. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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When applying machine learning technology to real-world applications, such as visual quality inspection, several practical issues need to be taken care of. One problem is posed by the reality that usually there are multiple human operators doing the inspection, who will inevitably contradict each other for some of the products to be inspected. In this paper an architecture for learning visual quality inspection is proposed which can be trained by multiple human operators, based on trained ensembles of classifiers. Most of the applicable ensemble techniques have however difficulties learning in these circumstances. In order to effectively train the system a novel ensemble framework is proposed as an enhancement of the grading ensemble technique—called active grading. The active grading algorithms are evaluated on data obtained from a real-world industrial system for visual quality inspection of the printing of labels on CDs, which was labelled independently by four different human operators and their supervisor, and compared to the standard grading algorithm and a range of other ensemble (classifier fusion) techniques.  相似文献   
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The dietary selenium (Se) intake in Belgium has been re-evaluated. Duplicate meal collection, wet acid destruction and flow injection hydride generation atomic absorption spectrometry were used as techniques. The daily intake ranged from 28.4 g (Liège, Walloon part of the country) to 61.1 g (Vilvoorde, central part of the country). Compared with intakes recently published for other countries, the actual Belgian value corresponds to intermediate ranges of Se intake.
Die aktuelle tägliche Selen-Aufnahme durch die Nahrung in Belgien, bestimmt durch doppelte Probenahme
Zusammenfassung Die Selen-Aufnahme durch die Nahrung in Belgien wurde neu bestimmt. Als Technik diente die doppelte Probenahme von Mahlzeiten, deren nasser Aufschluß und die Fließ-Injektions AAS mit Hydridgeneration. Die tägliche Aufnahme schwankt zwischen 28,4 und 61, 1 g. Im Vergleich zu Daten, die neuerdings aus anderen Ländern publiziert wurden, liegen die derzeitigen Werte aus Belgien im Mittelbereich.
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Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy-based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu-Zr nanoglass synthesized by magnetron sputtering. These analyses provide first-time in-depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time-of-flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable.  相似文献   
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The electrochemical behavior of copper oxide nanoparticles is investigated at both the single particle and at the ensemble level in neutral aqueous solutions through the electrode‐particle collision method and cyclic voltammetry, respectively. The influence of Cl? and NO3? anions on the electrochemical processes occurring at the nanoparticles is further evaluated. The electroactivity of CuO nanoparticles is found to differ between the two types of experiments. At the single‐particle scale, the reduction of the CuO nanoparticles proceeds to a higher extent in the presence of chloride ion than of nitrate ion containing solutions. However, at the multiparticle scale the CuO reduction proceeds to the same extent regardless of the type of anions present in solution. The implications for assessing realistically the environmental fate and therefore the toxicity of metal‐based nanoparticles in general, and copper‐based nanoparticles in particular, are discussed.  相似文献   
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