Electromagnetic Pulse Propagation over Nonuniform Earth Surface: Numerical Simulation

We simulate EM pulse propagation along the nonuniform earth surface using so called time-domain parabolic equation. To solve it by finite differences, we introduce a time-domain analog of the impedance boundary condition and a nonlocal BC of transparency reducing open computational domain to a strip of finite width. Numerical examples demonstrate influence of soil conductivity on the wide-band pulse waveform. For a high-frequency modulated EM pulse, we develop an asymptotic approach based on the ray structure of the monochromatic wave field at carrier frequency. This radically diminishes the computation costs and allows for pulsed wave field calculation in vast domains measured by tens of thousands wavelengths

Comment on ``Exact three-dimensional wave function and the on-shell t matrix for the sharply cut-off Coulomb potential: Failure of the standard renormalization factor''

The solutions analytically derived by Gloeckle et al. [Phys. Rev. C79, 044003 (2009)] for the three-dimensional wave function and on-shell t matrix in the case of scattering on a sharply cut-off Coulomb potential appear to be fallacious. And their renormalization factor lacks mathematical grounds.Comment: 5 page

MANAGEMENT ACTIVITIES EFFECTIVENESS IN MODERN RUSSIAN INSTITUTION IN THE CONTEXT OF HEAD WORKPLACE MODELING

Purpose: The scientific approach to the organization of labor and the workplace of the institution head involves the search for the most optimal model or technique acceptable to the Russian conditions within the current management culture, traditional views on the nature of managerial work, the scale and effectiveness of management activities. Methodology: Methodological guidelines for the study of workplaces’ organization of credit and financial institutions’ heads are based on the provisions of modern ergonomics and the principles of a system-based approach, allowing justifying as a significant one the environment-oriented approach. Result: The obtained results served as the basis for the development of appropriate recommendations to optimize the current situation in the context of eliminating existing gaps and problems in the credit and financial sector of the Russian economy from the standpoint of optimizing the process of organizing working places for managers of institutions in this profile. Applications: This research can be used for universities, teachers, and students. Novelty/Originality: In this research, the model of the Management Activities Effectiveness in Modern Russian Institution in the context of Head Workplace Modeling is presented in a comprehensive and complete manner

Predictors for outcome after surgery for traumatic acute subdural hematoma

Introduction: Acute traumatic subdural hematoma (ASDH) is one of the most frequent conditions in neurosurgery demanding emergency surgery. The aim of the study was to identify factors influencing outcome in patients who had surgery for evacuation of ASDH.Methods: From 2005 to 2012 eighty-five patients at age above 18 years had surgery for evacuation of ASDH. Outcome was measured according GOS at discharge and was dichotomized as “favorable outcome” (GOS 4 to 5) and “unfavorable outcome” (GOS 1 to 3). These factors were evaluated with univariate and logistic regression analysis for significance with outcome.Results: The mean age of the 85 patients was 62.7 years (SD±18.5). 45.9% patients were with favorable outcome and 54.1% had unfavorable outcome. Patients with GCS score 3-8 (54.1%) had 80.4% unfavorable outcome whereas 78.6% of patients with GCS score 13-15 (32.9%) had favorable outcome. All patients with nonreactive pupils (bilaterally or unilaterally -31.8%) had unfavorable outcome whereas patients (36.5%) with both reactive pupils (36.5%) had in 80.6% favorable outcome. All patients (40%) with Rotterdam CT scores 5 and 6 had unfavorable outcome. The factors determining outcome were admission GSC score, Rotterdam CT scores, and prothrombin time.Conclusion: Patients who have GSC score of 3, unresponsive pupil(s) or have Rotterdam CT scores 5 and 6 have little chance of survival. Patients with coagulopathy have two times more unfavorable outcome. The patients with ASDH should have surgery as soon as possible after correction of vital parameters in order to avoid deterioration which can be very rapid and irreversible

Algorithm of Key Words Search Based on Graph Model of Linguistic Corpus

One of the problems of computer corpus linguistics is an automatic determination of keywords inthe text. The solution is a statistical method based on calculation of various frequency characteristics of the text. In this case, the most commonly used model is a “bag of words”, which does not take into account the order of words in the text. In this paper, we propose a graph model of the text that allows us to calculate the frequency characteristics of words in the text not only within the framework of the “word bag” model, but with respect to location of pairs of owls in some common part of the text, for example, in one sentence. To work with such a model, a software model is constructed in the form of a database schema intended for storing various statistical text information. Taking into account such a data model, the article proposes an algorithm for determining the keywords of the text, the implementation of which is performed in the Python programming language. When analyzing a document d of linguistics corpus D, our algorithm creates a list of about 40 words with the largest measure tf-idf, and choise from them 20 words, which are more often used in the document d. We regard these words as vertices of some graph G, and the multiplicity of the edge, connecting the vertices t and t’ is equal to the number of sentences in document d, containing both these words. Approximately 10 vertices of the graph with the greatest degree are selected. The words corresponding to these vertices are taken for key words of document d

Study of the Effect of Two Phases in Li4SiO4–Li2SiO3 Ceramics on the Strength and Thermophysical Parameters

This research was funded by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (No. BR11765580). The research of the team from Latvia (A.M., V.P. and A.I.P.) has been carried out within the framework of the EUROfusion Consortium, funded by the European Union via the Euratom Research and Training Programme (Grant Agreement No. 101052200—EUROfusion). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neither the European Union nor the European Commission can be held responsible for them. The research was partly (A.M., V.P. and A.I.P.) performed in the Center of Excellence of the Institute of Solid State Physics, University of Latvia, supported through European Unions Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2.The paper studies the effect of Li2SiO3/Li4SiO4 phase formation in lithium-containing ceramics on the strength and thermophysical characteristics of lithium-containing ceramics, which have great prospects for use as blanket materials for tritium propagation. During the phase composition analysis of the studied ceramics using the X-ray diffraction method, it was found that an increase in the lithium component during synthesis leads to the formation of an additional orthorhombic Li2SiO3 phase, and the main phase in ceramics is the monoclinic Li4SiO4 phase. An analysis of the morphological features of the synthesized ceramics showed that an increase in the Li2SiO3 impurity phase leads to ceramic densification and the formation of impurity grains near grain boundaries and joints. During determination of the strength characteristics of the studied ceramics, a positive effect of an increase in the Li2SiO3 impurity phase and dimensional factors on the strengthening and increase in the resistance to external influences during compression of ceramics was established. During tests for resistance to long-term thermal heating, it was found that for two-phase ceramics, the decrease in strength and thermophysical characteristics after 500 h of annealing was less than 5%, which indicates a high resistance and stability of these ceramics in comparison with single-phase orthosilicate ceramics. © 2022 by the authors. --//-- This is an open access article Kozlovskiy A., Shlimas D.I., Zdorovets M.V., Moskina A., Pankratov V., Popov A.I. "Study of the Effect of Two Phases in Li4SiO4–Li2SiO3 Ceramics on the Strength and Thermophysical Parameters" (2022) Nanomaterials, 12 (20), art. no. 3682, DOI: 10.3390/nano12203682 published under the CC BY 4.0 licence.European Commission 101052200—EUROfusion; Ministry of Education and Science of the Republic of Kazakhstan BR11765580; institute of Solid-State Physics, University of Latvia has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase 2 under grant agreement No. 739508, project CAMART2.