6,977 research outputs found

    Effect of Unfolding on the Spectral Statistics of Adjacency Matrices of Complex Networks

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    Random matrix theory is finding an increasing number of applications in the context of information theory and communication systems, especially in studying the properties of complex networks. Such properties include short-term and long-term correlation. We study the spectral fluctuations of the adjacency of networks using random-matrix theory. We consider the influence of the spectral unfolding, which is a necessary procedure to remove the secular properties of the spectrum, on different spectral statistics. We find that, while the spacing distribution of the eigenvalues shows little sensitivity to the unfolding method used, the spectral rigidity has greater sensitivity to unfolding.Comment: Complex Adaptive Systems Conference 201

    Towards Understanding Egyptian Arabic Dialogues

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    Labelling of user's utterances to understanding his attends which called Dialogue Act (DA) classification, it is considered the key player for dialogue language understanding layer in automatic dialogue systems. In this paper, we proposed a novel approach to user's utterances labeling for Egyptian spontaneous dialogues and Instant Messages using Machine Learning (ML) approach without relying on any special lexicons, cues, or rules. Due to the lack of Egyptian dialect dialogue corpus, the system evaluated by multi-genre corpus includes 4725 utterances for three domains, which are collected and annotated manually from Egyptian call-centers. The system achieves F1 scores of 70. 36% overall domains.Comment: arXiv admin note: substantial text overlap with arXiv:1505.0308

    New Heterocyclic Syntheses from Pyridinethiones: an Efficient Route for the Syntheses of Some Novel Azo Derivatives of Thieno[2,3-b]pyridine as Potential Anti-bacterial and Anti-cancer Agents

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    Derivatives of a heterocyclic system 3-(pyrrol-1-yl)thieno[2,3-b]pyridine 5 and 6 carrying various substituents in the position 2 were synthesized. Some of these products were used to build up a variety of nitrogen- and/or oxygen-containing heterocyclic rings in that position. The electronic configurations of selected products were investigated using the AM1 semi-emperical molecular orbital method. Considerable variations in the magnitude and oriention of the dipole moment were observed. Further, the relative stability of the structures was investigated at physiological conditions via calculation of the electrostaticcomponent of the solvation free energy. The synthesized series showed favourable solvation free energies which were within the range from –30 to –23 kcal/mol.The high polarity and favourable solvation free energychanges at physiological conditions suggest that substitutionin the position 2 could enhance the biological activity of the 3-(pyrrol-1-yl)thieno[2,3-b]pyridine derivatives
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