168,427 research outputs found
Investigation of the influence of external factors on the potential performance of a person at the computer and his brain activity
No full textMarchuk A. Investigation of the influence of external factors on the potential performance of a person at the computer and his brain activity / A. Marchuk, Ya. Davydov ; sci. advisors L. Vasylieva, I. Staskevych // Black Sea Science 2021. Information Technology, Automation and Robotics : рroc. of the Intern. Competition of Student Scientific Works / Odessa Nat. Acad. of Food Technologies ; eds. B. Yegorov, M. Mardar, S. Kotlyk [et al.]. – Odessa : ONAFT, 2021. – P. 333-344 : fig. – Ref.: 21 tit.This study aims to create tools to maximize the potential performance
of a person at the computer. The effects of mental fatigue on efficiency and,
consequently, on productivity is difficult to overestimate. People who work a lot at
the computer are particularly prone to high cognitive load and, as a result, loss of
motivation and poor performance. In this work, experiments were performed to
change the usual parameters of the environment during the working day and
investigated their impact on the efficiency of human interaction with the computer
and its electrical activity of the brain. The hypothesis of a correlation between
electroencephalographic data collected using a portable neurointerface and mental
fatigue has been partially confirmed. The created software-hardware system based
on the obtained results will be a useful tool for optimizing the working conditions of
employees in the IT field and others
A 2 h periodic variation in the low-mass X-ray binary Ser X-1
No full textSpectroscopy of the low-mass X-ray binary Ser X-1 using the Gran Telescopio Canarias have revealed a ?2 h periodic variability that is present in the three strongest emission lines. We tentatively interpret this variability as due to orbital motion, making it the first indication of the orbital period of Ser X-1. Together with the fact that the emission lines are remarkably narrow, but still resolved, we show that a main-sequence K dwarf together with a canonical 1.4 M? neutron star gives a good description of the system. In this scenario, the most likely place for the emission lines to arise is the accretion disc, instead of a localized region in the binary (such as the irradiated surface or the stream-impact point), and their narrowness is due instead to the low inclination (?10°) of Ser X-1
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Dr. Edward P. Wimberly, ITC, July 2011
No full textThis video is a conversation with Dr. Edward P. Wimberly. Dr. Wimberly talks about his book, "No Shame in Wesley's Gospel: A Twenty-First Century Pastoral Gospel". Brad Ost, AUC Woodruff Library, is the interviewer
Universal Statistical Properties of Inertial-particle Trajectories in Three-dimensional, Homogeneous, Isotropic, Fluid Turbulence
No full textWe obtain new universal statistical properties of heavy-particle trajectories in three-dimensional, statistically steady, homogeneous, and isotropic turbulent flows by direct numerical simulations. We show that the probability distribution functions (PDFs) P(Φ), of the angle Φ between the Eulerian velocity u and the particle velocity v, at a point and time, scales as P(Φ) ∼Φ−, with a new universal exponent ≃ 4
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Threshold electrolyte concentration and dispersive potential in relation to CROSS in dispersive soils
No full textWe have used the newly developed concept of CROSS (cation ratio of soil structural stability) instead of SAR (sodium adsorption ratio) in our study on dispersive soils. CROSS incorporates the differential dispersive powers of Na and K and the differences in the flocculating effects of Ca and Mg. The CROSS of the dispersed soil solutions, from the differently treated soils of three soil types varying in clay content, mineralogy, and organic matter, was highly correlated with the amount of clay dispersed. The relation between CROSS and exchangeable cation ratio depended on soil type, and particularly organic matter and the content and mineralogy of clay. Threshold electrolyte concentration of the flocculated suspensions was significantly correlated with CROSS of the dispersed suspensions. The cationic flocculating charge of the flocculated suspensions, which incorporates the individual flocculating powers of the cations, was significantly correlated with CROSS. However, these types of relations will depend on several soil factors even within a given soil class. Therefore, we have derived the dispersive potential of an individual soil from which we calculated the required cationic amendments to maintain flocculated soils and their structural integrity.Alla Marchuk and Pichu Rengasam
Cation ratio of soil structural stability (CROSS)
No full textSodium salts tend to dominate salt-affected soils and groundwater in Australia and therefore, sodium adsorption ratio (SAR) is being used to parameterize soil sodicity and the effects of sodium on soil structure. Recent reports, however, now draw attention to elevated concentrations of potassium and/or magnesium in some soils naturally and also as a result of increasing irrigation with recycled water in Australia. Therefore, there is a need to derive and define a new ratio of these cations in place of SAR, which will indicate the effects of Na and K on clay dispersion and Ca and Mg on flocculation. Rengasamy and Sumner (1998) derived the flocculation power of these cations and on this basis Rengasamy (unpublished) defined the cation ratio of soil structural stability (CROSS). This paper gives the results of an experiment conducted on ten soil samples on hydraulic conductivity using a number of artificially prepared irrigation waters, containing different proportions of the cations Ca, Mg, K and Na. The relative changes in hydraulic conductivity of these soils reflected the flocculating power of the cations, compared to the control treatment of using CaCl2 solution. Clay dispersion was found to be highly correlated to CROSS rather than to SAR.Alla G. Marchuk and Pichu Rengasamyhttp://trove.nla.gov.au/work/37679232http://www.iuss.org/19th%20WCSS/19th%20WCSS_Handbook_REAL%20HANDBOOK_V10_BACK%20COVER%20change.pd
Genuine memoirs of the celebrated Miss Maria Brown [electronic resource] : Exhibiting the life of a courtezan, in the most fashionable scenes of dissipation. Published by the author of a W** of P*** In two volumes.
No full textAuthor of a W** of P*** [Woman of Pleasure] = John Cleland, to whom this work is sometimes attributed.Electronic reproduction.English Short Title Catalog,Reproduction of original from British Library
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