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131.
The paper is concerned with system reduction by statistical methods and, in particular, by the optimal prediction method introduced
in (Chorin, A.J., Hald, O.H., Kupferman, R., Optimal prediction with memory, Phys. D 166:239–257, 2002). The optimal prediction
method deals with problems that possess large and small scales and uses the conditional expectation to model the influence
of the small scales on the large ones.
In the current paper, we develop a different variant of the optimal prediction method as well as introduce and compare several
approximations of this method. We apply the original and modified optimal prediction methods to a system of ODEs obtained
from a particle method discretization of a hyperbolic PDE and demonstrate their performance in a number of numerical experiments. 相似文献
132.
Alina O. Koriabkina Danny Schuring Arthur M. de Jong Rutger A. van Santen 《Topics in Catalysis》2003,24(1-4):103-113
The influence of the loading on the self-diffusion of 3-methylpentane within silicalite-1 has been studied with Positron Emission Profiling technique. A monotonous decrease in the self-diffusivities of alkane was observed with zeolite loading, which could be approximated by a stretched exponential. As a consequence, the apparent activation energy increases with partial pressure. 相似文献
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Fabio Bellavia Antonino Cacioppo Carmen Alina Lupaşcu Pietro Messina Giuseppe Scardina Domenico Tegolo Cesare Valenti 《Computer methods and programs in biomedicine》2014
We aim to describe a new non-parametric methodology to support the clinician during the diagnostic process of oral videocapillaroscopy to evaluate peripheral microcirculation. Our methodology, mainly based on wavelet analysis and mathematical morphology to preprocess the images, segments them by minimizing the within-class luminosity variance of both capillaries and background. Experiments were carried out on a set of real microphotographs to validate this approach versus handmade segmentations provided by physicians. By using a leave-one-patient-out approach, we pointed out that our methodology is robust, according to precision–recall criteria (average precision and recall are equal to 0.924 and 0.923, respectively) and it acts as a physician in terms of the Jaccard index (mean and standard deviation equal to 0.858 and 0.064, respectively). 相似文献
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Kerrie Unsworth Elisa AdriasolaAmber Johnston-Billings Alina DmitrievaMelinda Hodkiewicz 《Reliability Engineering & System Safety》2011,96(11):1474-1481
Many have recognized the need for high quality data on assets and the problems in obtaining them, particularly when there is a need for human observation and manual recording. Yet very few have looked at the role of the data collectors themselves in the data quality process. This paper argues that there are benefits to more fully understanding the psychological factors that lay behind data collection and we use goal hierarchy theory to understand these factors. Given the myriad of potential reasons for poor-quality data it has previously proven difficult to identify and successfully deploy employee-driven interventions; however, the goal hierarchy approach looks at all of the goals that an individual has in their life and the connections between them. For instance, does collecting data relate to whether or not they get a promotion? Stay safe? Get a new job? and so on. By eliciting these goals and their connections we can identify commonalities across different groups, sites or organizations that can influence the quality of data collection. Thus, rather than assuming what the data collectors want, a goal hierarchy approach determines that empirically. Practically, this supports the development of customized interventions that will be much more effective and sustainable than previous efforts. 相似文献
138.
Exfoliated graphitic nanoplatelets (xGnPs) show adsorption capability and adsorption efficiency for lead removal from water, the adsorption being influenced by the solution pH value and the xGnPs surface characteristics, which are controlled by their treatment processing. The adsorption isotherms were described by both Langmuir and Freundlich models. These results suggest that xGnPs are remarkable lead adsorbents, having potential applications in environmental protection. 相似文献
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Dr. Camelia Vlad Kathrin Lindner Dr. Christiaan Karreman Dr. Stefan Schildknecht Prof. Marcel Leist Nick Tomczyk Dr. John Rontree Dr. James Langridge Dr. Karin Danzer Dr. Thomas Ciossek Dr. Alina Petre Prof. Dr. Michael L. Gross Prof. Dr. Bastian Hengerer Prof. Dr. Michael Przybylski 《Chembiochem : a European journal of chemical biology》2011,12(18):2706-2706