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681.
Tarek R. Besold Artur d’Avila Garcez Keith Stenning Leendert van der Torre Michiel van Lambalgen 《Minds and Machines》2017,27(1):37-77
This article aims to achieve two goals: to show that probability is not the only way of dealing with uncertainty (and even more, that there are kinds of uncertainty which are for principled reasons not addressable with probabilistic means); and to provide evidence that logic-based methods can well support reasoning with uncertainty. For the latter claim, two paradigmatic examples are presented: logic programming with Kleene semantics for modelling reasoning from information in a discourse, to an interpretation of the state of affairs of the intended model, and a neural-symbolic implementation of input/output logic for dealing with uncertainty in dynamic normative contexts. 相似文献
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We describe the parallel full-f gyrokinetic particle-in-cell plasma simulation code ELMFIRE and the issue of solving an electrostatic potential from particle data distributed across several MPI (Message Passing Interface) processes. The potential is solved through a linear system with a strongly sparse matrix and ELMFIRE stores data of the estimated non-zero diagonals of the whole matrix in every MPI process. We present and compare several memory efficient structures for gathering the matrix data while keeping only a local part of the matrix in each process. We also demonstrate that these alternative structures improve scalability, thus enabling ELMFIRE to use more MPI processes and a finer time and space scale than before without sacrificing performance. 相似文献
685.
Emanuel Pacheco Freire Artur Ziviani Ronaldo Moreira Salles 《Journal of Network and Systems Management》2009,17(1-2):53-72
Skype is a Voice over IP (VoIP) Internet application that is gaining huge popularity in recent years. A key point to Skype popularity is its capability to dynamically adapt itself to operate behind firewalls or network proxies. A common way adopted by Skype to delude these network devices is to use port 80, normally expected to comprise HTTP traffic. In this paper, we propose metrics and investigate statistical tests intended to clearly distinguish Skype flows from HTTP traffic. We validate our study using real-world experimental datasets gathered at a commercial Internet Service Provider (ISP). Our experimental results suggest that the proposed methodology may be seen as a promising building block towards a system to detect general protocol anomalies in HTTP traffic. 相似文献
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Ana C. Estrada Mário M. Q. Simões Isabel C. M. S. Santos M. Graça P. M. S. Neves Artur M. S. Silva José A. S. Cavaleiro Ana M. V. Cavaleiro 《Catalysis Letters》2009,128(3-4):281-289
The oxidation of 1H-indene and 1,2-dihydronaphthalene with hydrogen peroxide in the presence of Mn(III) or Fe(III) substituted Keggin-type polyoxotungstates is described. The products obtained depend on the catalyst and reaction conditions. Ring cleavage was observed, affording dialdehydes under mild and environmentally friendly conditions. Other main products were the α-hydroxy-ketones. The resulting epoxides seem to be intermediates to other oxygenated products. 相似文献
689.
Artur J. Martins Jos M. Lorenzo Daniel Franco Antnio A. Vicente Rosiane L. Cunha Lorenzo M. Pastrana John Quiones Miguel A. Cerqueira 《European Journal of Lipid Science and Technology》2019,121(11)
Obesity and cardiovascular diseases are among the most worrying health problems worldwide. Dietary habits can be catalysts for the rise of these health issues in western countries. In this work, a meat product (pork patties) commonly elaborated with a high fraction of saturated fat is reformulated with an oleogel based on linseed oil (rich in polyunsaturated fatty acids). The oleogel is used for the partial replacement of the solid fat fraction present in pork patties (H‐25 for 25% and H‐75 for 75% of replacement). Incorporation of oleogels results in the modification of the fatty acid profile and in the significant decrease of the omega‐6/omega‐3 ratio. Results show that for both degrees of fat substitution, there are no differences between the patties produced with oleogel incorporation and the control, regarding textural parameters such as hardness, cohesiveness, and chewiness. Overall, samples with less amount of oleogel (H‐25) are well classified in the acceptance and preference tests, despite the clear preference among the sensorial panel toward the control samples. These results show the feasibility of introducing oleogels as a fat replacer in the manufacturing process of pork patties, though there is still work to be done regarding some of their sensorial attributes. Practical Applications: The purpose of this work is focused on the study of the properties of meat patties after the replacement of saturated fat with a multicomponent oleogel, foreseeing the hamburger production. The results show that the oleogel incorporation in meat patties is possible at the industrial level without additional unitary steps during meat patty production. Based on this work it is possible to produce meat patties with adjusted fatty acids profiles. 相似文献
690.
Caisa Andersson Lars Järnström Andrew Fogden Isabel Mira Wolfgang Voit Sebastian Zywicki Artur Bartkowiak 《Packaging Technology and Science》2009,22(5):275-291
The replacement of flexible polyolefin barrier layers with novel, thin, functional polymer coatings in the production of paperboard packaging involves the risk of deteriorated barrier and mechanical properties during the converting process. Local defects or cracks in the protective barrier layer can arise because of the stress induced in creasing and folding operations. In this study, the incorporation of microencapsulated self‐healing agents in coating formulations applied both by spot‐ and uniform‐coating techniques was studied. The preparation process of microcapsules with a hydrophobic core surrounded by a hydrophobically modified polysaccharide membrane in aqueous suspension was developed to obtain capsules fulfilling both the criteria of small capsule size and reasonably high solids content to match the requirements set on surface treatment of paperboard for enhancement of packaging functionality. The survival of the microcapsules during application and their effectiveness as self‐healing agents were investigated. The results showed a reduced tendency for deteriorated barrier properties and local termination of cracks formed upon creasing. The self‐healing mechanism involves the rupture of microcapsules local to the applied stress, with subsequent release of the core material. Crack propagation is hindered by plasticization of the underlying coating layer, while the increased hydrophobicity helps to maintain the barrier properties. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献