ALBERT

Description: Information, Vol. 9, Pages 128: Key Concept Identification: A Comprehensive Analysis of Frequency and Topical Graph-Based Approaches Information doi: 10.3390/info9050128 Authors: Muhammad Aman Abas bin Md Said Said Jadid Abdul Kadir Israr Ullah Automatic key concept extraction from text is the main challenging task in information extraction, information retrieval and digital libraries, ontology learning, and text analysis. The statistical frequency and topical graph-based ranking are the two kinds of potentially powerful and leading unsupervised approaches in this area, devised to address the problem. To utilize the potential of these approaches and improve key concept identification, a comprehensive performance analysis of these approaches on datasets from different domains is needed. The objective of the study presented in this paper is to perform a comprehensive empirical analysis of selected frequency and topical graph-based algorithms for key concept extraction on three different datasets, to identify the major sources of error in these approaches. For experimental analysis, we have selected TF-IDF, KP-Miner and TopicRank. Three major sources of error, i.e., frequency errors, syntactical errors and semantical errors, and the factors that contribute to these errors are identified. Analysis of the results reveals that performance of the selected approaches is significantly degraded by these errors. These findings can help us develop an intelligent solution for key concept extraction in the future.

Description: Author(s): A. Said Mohamed, M. A. Herrada, A. M. Gañán-Calvo, and J. M. Montanero The convective-to-absolute instability transition in an Oldroyd-B capillary jet subject to unrelaxed axial stress is examined theoretically. There is a critical Weber number below which the jet is absolutely unstable under axisymmetric perturbations. We analyze the dependence of this critical parame… [Phys. Rev. E 92, 023006] Published Wed Aug 05, 2015

Description: Detecting the cognitive profiles of learners is an important step towards personalized and adaptive learning. Electroencephalograms (EEG) have been used to detect the subject’s emotional and cognitive states. In this paper, an approach for detecting two cognitive skills, focused attention and working memory, using EEG signals is proposed. The proposed approach consists of the following main steps: first, subjects undergo a scientifically-validated cognitive assessment test that stimulates and measures their full cognitive profile while putting on a 14-channel wearable EEG headset. Second, the scores of focused attention and working memory are extracted and encoded for a classification problem. Third, the collected EEG data are analyzed and a total of 280 time- and frequency-domain features are extracted. Fourth, several classifiers were trained to correctly classify and predict three levels (low, average, and high) of the two cognitive skills. The classification accuracies that were obtained on 86 subjects were 84% and 81% for the focused attention and working memory, respectively. In comparison with similar approaches, the obtained results indicate the generalizability and suitability of the proposed approach for the detection of these two skills. Thus, the presented approach can be used as a step towards adaptive learning where real-time adaptation is to be done according to the predicted levels of the measured cognitive skills.

Description: ZnO nanorods (NRs) with an average length and diameter of 186 and 20 nm, respectively, were prepared through a mild solvothermal route and used as photocatalysts either as dispersed powder or immobilized on glass slides. The ZnO NRs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Dispersed ZnO NRs and, to a lesser extent, immobilized ZnO NRs were demonstrated to exhibit high photocatalytic activity under simulated sunlight of low intensity (5.5 mW/cm2) both for the degradation of the Orange II dye and for Escherichia coli bacterial decontamination (2.5-fold survival decrease after 180 min irradiation for immobilized NRs). SEM, atomic force microscopy (AFM), fluorescence spectroscopy, and epifluorescence microscopy demonstrate that cell surface damages are responsible of bacterial inactivation. The immobilized ZnO NRs could be reused up to five times for bacterial decontamination at comparable efficiency and therefore have great potential for real environmental applications.

Description: The Multi-angle Imaging SpectroRadiometer (MISR) sensor onboard the Terra satellite provides high accuracy albedo products. MISR deploys nine cameras each at different view angles, which allow a near-simultaneous angular sampling of the surface anisotropy. This is particularly important to measure the near-instantaneous albedo of dynamic surface features such as clouds or sea ice. However, MISR’s cloud mask over snow or sea ice is not yet sufficiently robust because MISR’s spectral bands are only located in the visible and the near infrared. To overcome this obstacle, we performed data fusion using a specially processed MISR sea ice albedo product (that was generated at Langley Research Center using Rayleigh correction) combining this with a cloud mask of a sea ice mask product, MOD29, which is derived from the MODerate Resolution Imaging Spectroradiometer (MODIS), which is also, like MISR, onboard the Terra satellite. The accuracy of the MOD29 cloud mask has been assessed as 〉90% due to the fact that MODIS has a much larger number of spectral bands and covers a much wider range of the solar spectrum. Four daily sea ice products have been created, each with a different averaging time window (24 h, 7 days, 15 days, 31 days). For each time window, the number of samples, mean and standard deviation of MISR cloud-free sea ice albedo is calculated. These products are publicly available on a predefined polar stereographic grid at three spatial resolutions (1 km, 5 km, 25 km). The time span of the generated sea ice albedo covers the months between March and September of each year from 2000 to 2016 inclusive. In addition to data production, an evaluation of the accuracy of sea ice albedo was performed through a comparison with a dataset generated from a tower based albedometer from NOAA/ESRL/GMD/GRAD. This comparison confirms the high accuracy and stability of MISR’s sea ice albedo since its launch in February 2000. We also performed an evaluation of the day-of-year trend of sea ice albedo between 2000 and 2016, which confirm the reduction of sea ice shortwave albedo with an order of 0.4–1%, depending on the day of year and the length of observed time window.

Description: Elderly Bedouin men in southern Israel are a unique traditional population living in remote unrecognized villages and experiencing rapid social transition, in addition to deep poverty and political tension. In this study, we aimed to explore stressful events, as self-defined by the participants, and the ways in which these men have coped with those stressful events. This study involved 12 men, aged 69–74, who participated in in-depth narrative interviews during which they were asked about transformative stressful events in their lives and how they had managed, understood, and utilized human capital, meaning-making, and other methods of coping. Analysis of the interviews revealed several themes: (a) the definition of stressful events within the cultural context, (b) the use of human capital to overcome those events, (c) the transformation of experience from hindsight into a didactic narrative that can be used to assign meaning to past events, which can then be passed on to the next generation, and (d) cultural transition as a catalyst for the creation of new understandings of events. This paper sheds new light on how elderly indigenous Bedouin men self-define stressful situations within a complex and unstable cultural context. This specific context, can help us to gain insight into how indigenous impoverished older men in similar contexts may self-define their stress and coping, based on the types of generalization accepted in qualitative research. The methodological contribution of this work lies in its use of narrative to culturally contextualize phenomenological meaning structures. Its theoretical contribution lies in its examination of the concept of stress within a specific cultural context.

Description: The objective of this work was to evaluate some of the important physical and mechanical properties of particleboard panels manufactured from three different cultivars of date palm (Phoenix dactylifera) fronds, namely Saqui, Barhi and Sukkari. Experimental panels were manufactured from hot water extracted and non-extracted, and fine and coarse particles of the raw material under two target panel densities of 650 and 750 kg/m3. Bending properties and internal bond strength, along with dimensional stability in the form of thickness swelling, water absorption, and linear expansion of the samples was tested. Based on the findings of this work, panels manufactured from high density level and Saqie cultivar, as well as fine particles, had better performance for their mechanical properties. The effect of hot water-treatment had less robust mechanical and physical properties. It appears that date palm fronds are underutilized resources that have the potential to be used in the manufacture of value-added panel products.

Description: Author(s): Nicholas P. Butch, Michael E. Manley, Jason R. Jeffries, Marc Janoschek, Kevin Huang, M. Brian Maple, Ayman H. Said, Bogdan M. Leu, and Jeffrey W. Lynn We experimentally investigate the symmetry in the hidden order (HO) phase of intermetallic URu 2 Si 2 by mapping the lattice and magnetic excitations via inelastic neutron and x-ray scattering measurements in the HO and high-temperature paramagnetic phases. At all temperatures, the excitations respect ... [Phys. Rev. B 91, 035128] Published Mon Jan 26, 2015

Description: Author(s): Sahan U. Handunkanda, Erin B. Curry, Vladimir Voronov, Ayman H. Said, Gian G. Guzmán-Verri, Richard T. Brierley, Peter B. Littlewood, and Jason N. Hancock Perovskite structured materials contain myriad tunable ordered phases of electronic and magnetic origin with proven technological importance and strong promise for a variety of energy solutions. An always-contributing influence beneath these cooperative and competing interactions is the lattice, who… [Phys. Rev. B 92, 134101] Published Thu Oct 01, 2015

Description: Author(s): Ioannis Brouzos, Alexej I. Streltsov, Antonio Negretti, Ressa S. Said, Tommaso Caneva, Simone Montangero, and Tommaso Calarco We apply the concept of quantum speed limit (QSL)—the minimal time needed to perform a driven evolution—to complex interacting many-body systems where the effects of interactions have to be taken into account. We introduce a general strategy to eliminate the detrimental effects of the interparticle … [Phys. Rev. A 92, 062110] Published Mon Dec 07, 2015