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About One Discrete Mathematical Model of Perfect Fluid

Open Journal of Modelling and Simulation 2016年第3期4卷 129-167页

作者： konstantin Eduardovich Plokhotnikov Moscow State University Moscow Russia

In work, it is constructed a discrete mathematical model of motion of a perfect fluid. The fluid is represented as an ensemble of identical so-called liquid particles, which are in the form of extended geometrical objects: circles and spheres for two-dimensional and three-dimensional cases, respectively. The mechanism of interaction between the liquid particles on a binary level and on the level of the n-cluster is formulated. This mechanism has previously been found by the author as part of the mathematical modeling of turbulent fluid motion. In the turbulence model was derived and investigated the potential interaction of pairs of liquid particles, which contained a singularity of the branch point. Exactly, this is possible to build in this article discrete stochastic-deterministic model of an ideal fluid. The results of computational experiment to simulate various kinds of flows in two-dimensional and three-dimensional ensembles of liquid particles are presented. Modeling was carried out in the areas of quadratic or cubic form. On boundary of a region satisfies the condition of elastic reflection liquid particles. The flows with spontaneous separation of particles in a region, various kinds of eddy streams, with the quite unexpected statistical properties of an ensemble of particles characteristic for the Fermi-Pasta-Ulam effect were found. We build and study the flow in which the velocity of the particles is calibrated. It was possible using the appropriate flows of liquid particles of the ensemble to demonstrate the possibility to reproduce any prescribed image by manipulating the parameters of the interaction. Calculations of the flows were performed with using MATLAB software package according to the algorithms presented in this article.

关键词： Perfect Fluid Discrete Model Liquid Particle Branch Point Turbulence Interaction in the Cluster The Laws of Conservation Stochastic and Deterministic Components of the Flow Computational Experiment The Separation of Particles The Effect of the Fermi-Pasta-Ulam Calibration of Particle Velocities

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Band Structure and Optical Gain of InGaAs/GaAsBi Type-Ⅱ Quantum Wells Modeled by the k·p Model

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Chinese Physics Letters 2018年第5期35卷 133-136页

作者： Chang Wang Wenwu Pan konstantin Kolokolov Shumin Wang Key Laboratory of Terahertz Solid-State Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 School of Physical Science and Technology Shanghai Tech University Shanghai 201210 University of Chinese Academy of Sciences Beijing 100190 Faculty of Physics M. V. Lomonosov Moscow State University Moscow 119991 Russia Department of Microtechnology and Nanoscience Chalmers University of Technology Gothenburg 41296 Sweden

Optical gains of type-Ⅱ In Ga As/Ga As Bi quantum wells（QWs） with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wave functions are calculated using the self-consistent k·p Hamiltonian, taking into account valence band mixing and the strain effect. Our calculations show that the M-shaped type-Ⅱ QWs are a promising structure for making 1.3 um lasers at room temperature because they can easily be used to obtain 1.3 um for photoluminescence with a proper thickness and have large wave-function overlap for high optical gain.

关键词： As Bi In Ga Band Structure and Optical Gain of InGaAs/GaAsBi Type Quantum Wells Modeled by the k p Model

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Elastodynamic Infinite Elements with Modified Bessel Shape Functions for Dynamic Soil-Structure Interaction

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Journal of Mechanics Engineering and Automation 2011年第1期1卷 38-43页

作者： konstantin Savkov Kazakov Structural Mechanics Dept. Higher School of Civil Engineering ＂L. Karavelov ＂ 175 Suhodolska Str. Sofia 1373 Bulgaria

The paper is devoted to formulations of decay and mapped elastodynamic infinite elements, based on modified Bessel shape functions. These elements are appropriate for Soil-Structure Interaction （SSI） problems, solved in time or frequency domain and can be treated as a new form of the recently proposed Elastodynamic Infinite Elements with United Shape Functions （EIEUSF） infinite elements. The formulation of 2D Horizontal type Infinite Elements （HIE） is demonstrated here, but by similar techniques 2D Vertical （VIE） and 2D Comer （CIE） Infinite Elements can also be formulated. Using elastodynamic infinite elements is the easier and appropriate way to achieve an adequate simulation including basic aspects of Soil-Structure Interaction. Continuity along the artificial boundary （the line between finite and infinite elements） is discussed as well and the application of the proposed elastodynamic infinite elements in the Finite Element Method （FEM） is explained in brief. Finally, a numerical example shows the computational efficiency of the proposed infinite elements.

关键词： Soil-structure interaction (SSI) wave propagation infinite elements finite element method (FEM) bessel functions.

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Effect of Force Adaptation in Mechanics

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Journal of Mechanics Engineering and Automation 2011年第3期1卷 163-180页

作者： konstantin Samson Ivanov Chair of Engineering Graphics and Applied Mechanics Faculty Information Technologies Almatinsky University of Power Engineering and Telecommunications Almaty 050026 Kazakhstan

Discovery of effect of force adaptation in mechanics is presented. The discovery is based on use of the mobile closed mechanical contour for force transfer from the mechanism input link to an output link, According to discovery the motion transfer can be carried out by Assur structural group in the form of the mobile closed contour, and the output link is the link with one degree of freedom. The received mechanical system includes an input link, an output link and the closed contour placed between them as fourth class Assur structural group. The kinematic chain has two degrees of freedom. However the closed contour imposes an additional constraint on relative motion of its links. The carried out discovery allows providing the variable transfer ratio only due to the variable external load. Mechanical properties of the closed contour allow providing the required transfer ratio independently, smart and automatically.

关键词： Force adaptation closed contour constraint.

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Sub-Saharan Countries in the Age of Informational Globalization： On Preservation of Cultural Identity

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International Relations and Diplomacy 2015年第1期3卷 19-27页

作者： konstantin A. Pantserev St. Petersburg State University St. Petersburg Russia

The paper is devoted to the problem of the development of information technologies in Sub-Saharan countries. The author comes to a conclusion that the up-to-date level of the development of information technologies in Sub-Saharan countries doesn＇t give us an opportunity to estimate the close equal integration of the region into the global information and communication space. African countries don＇t have appropriate financial and technological resources which seem to be necessary when creating the well-developed information and telecommunication infrastructure on their territory. The author argues that in order to reach the level of the development of well-developed nations African states are forced to seek the aid of Western countries which use the technological and financial dependence of their African partners as the strong instrument of preservation of their influence in the region. In current circumstances it would be very difficult for Afxican countries to create a self-reliant information society and to preserve their cultural identity in the upcoming information age.

关键词： Sub-Saharan countries information society information technologies information space Africa

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Promoting axonal regeneration following nerve surgery： a perspective on ultrasound treatment for nerve injuries

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Neural Regeneration Research 2018年第9期13卷 1530-1533页

作者： konstantin D. Bergmeister Simeon C. Daeschler Patrick Rhodius Philipp Schoenle Arne Bocker Ulrich Kneser Leila Harhaus Department of Hand Plastic and Reconstructive Surgery Burn Center Department of Plastic and Hand Surgery University of Heidelberg BG Trauma Hospital Ludwigshafen Ludwigshafen Germany

Nerve injury is often associated with limited axonal regeneration and thus leads to delayed or incomplete axonal *** a consequence of slow nerve regeneration,target muscle function is often insufficient and leads to a lifelong ***,the diagnosis of nerve injuries has been improved and likewise surgical reconstruction has undergone significant ***,the problem of slow nerve regeneration has not been *** a recent meta-analysis,we have shown that the application of low-intensity ultrasound promotes nerve regeneration experimentally and thereby can improve functional *** we want to demonstrate the experimental effect of low intensity ultrasound on nerve regeneration,the current state of investigations and its possible future clinical applications.

关键词： peripheral nerve injuries nerve regeneration reinnervation experimental studies low-intensityultrasound adjunct treatment nerve reconstruction nerve surgery axonal injury

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Mathematical modelling of the progression of active tuberculosis:Insights from fluorography data

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Infectious Disease Modelling 2022年第3期7卷 374-386页

作者： konstantin konstantinovich Avilov Alexei Alexeevich Romanyukha Evgeny Mikhailovich Belilovsky Sergey Evgenevich Borisov Institute for Numerical Mathematics Russian Academy of Sciences8Gubkina Str.Moscow119333Russia Moscow Research and Clinical Center for Tuberculosis Control of the Moscow Government Department of Health 10Stromynka Str.Moscow107076Russia

Little is known about the dynamics of the early stages of untreated active pulmonary tuberculosis:unknown are both the rates of progression and the model“scheme”.The“parallel”scheme assumes that infectiousness of tuberculosis cases is effectively predefined at the onset of the disease,and the“serial”scheme considers all cases to be noninfectious at the onset,with some of them later becoming *** aim was to estimate the progression of the early stages of pulmonary tuberculosis using data from a present-day *** used the routine notification data from Moscow,Russia,2013e2018 that contained the results and time of the last fluorographic screening preceding the detection of tuberculosis *** provided time limits on the duration of untreated *** of TB progression under both models were *** the goodness of fit to the data,we could prefer neither the“parallel”,nor the“serial”model,although the latter had a bit worse *** the other hand,the observed rise in the fraction of infectious tuberculosis cases with the time since the last screening was explained by the“serial”model in a more plausible way e as gradual progression of some cases to ***“parallel”model explained it through less realistic quick removal of non-infectious cases and accumulation of the infectious *** results demonstrate the potential of using such detection data enriched with reassessments of the previous screenings.

关键词： Natural history of tuberculosis(TB) Mathematical modeling Minimal tuberculosis Model structure Fluorographic screening data

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Modeling of Roll-Heave-Pitch Motions of a Ram Wing Translating over Non-uniform Surface

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Journal of Marine Science and Application 2019年第2期18卷 123-130页

作者： konstantin I.Matveev School of Mechanical and Materials Engineering Washington State University

Ground-effect vehicles flying close to water or ground often employ ram wings which generate aerodynamic lift primarily on their lower *** subject of this paper is the 3-DOF modeling of roll,heave,and pitch motions of such a wing in the presence of surface waves and other ground *** potential-flow extreme-ground-effect theory is applied for calculating unsteady pressure distribution under the wing which defines instantaneous lift force and *** simulations of a selected ramwing configuration are carried out in the presence of surface waves of various headings and wavelengths,as well as for transient flights over a ground *** largest amplitudes of the vehicle motions are observed in beam waves when the periods of the encounter are *** effects are more pronounced for pitch angles than for roll and *** present method can be adapted for modeling of air-supported lifting surfaces on fast marine vehicles.

关键词： Ramwing Ground effect Seakeeping Dynamics Modeling Potential flow theory

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Comparative Analysis of Site Preparation Costs of Poplar Plantations Establishment by Various Technological Schemes

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Journal of Agricultural Science and Technology(B) 2017年第2期7卷 125-138页

作者： konstantin Marinov Velika Jordanova Faculty of Forestry University of Forestry Sofia 1797 Bulgaria

In this work, the costs for machinery and all means for site preparation of forest clearings for afforestation with intensivepoplar plantations were studied by applying various technological schemes. For this purpose, three technological schemes （TS1,TS2and TS3）, applying in Bulgaria, were studied. By applying the respective technological scheme, the site preparation was performedentirely with a milling aggregate PT-400, equipped with multifunctional forest tiller FAE-300/S. The processes of shredding stumps,mulching clearing debris and bushes, and primary tillage of the soil up to depth of 50 cm were examined. The survey was conductedin poplar clearings along the river Danube, over alluvial moderately moist soil. A new categorization of the poplar clearings isproposed depending on the operating conditions. The performance of the milling unit and the relative costs for labor, machinery andmeans for site preparation per unit area were defined. Depending on the category of poplar clearings, total cost for site preparationapplying the studied technology vary between 27.6 h/ha and 29.3 h/ha, which at current prices of 53.5 ∈/h for the operation of PT-400with FAE 300/S is between ∈1,478/ha and ∈1,569/ha. To conduct comparative analysis of the new technology and the oldtechnologies under similar operating conditions, the relatively costs for site preparation of the previously applied technologies whichuse rotary and tooth uprooter machines are defmed. According to the applied technological scheme and used machines in differentcategories, clearings costs for land preparation vary between ∈1,230/ha and ∈3,300/ha. Based on comparative analysis, it is designeda new technological scheme for afforestation with poplar plantations in riverside clearings, where by ensuring high quality work, thecosts for site preparation become lower （24.2-25.9 h/ha） and thus cost from ∈993/ha to 61,084/ha is achieved.

关键词： Forest plantations, afforestation, technological scheme for site preparation, costs, forest machinery.

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Hepatobiliary system and intestinal injury in new coronavirus infection(COVID-19):A retrospective study

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World Journal of Clinical Cases 2023年第10期11卷 2226-2236页

作者： konstantin V Kozlov konstantin V Zhdanov Anna K Ratnikova Vyacheslav A Ratnikov Artem V Tishkov Vladimir Grinevich Yuriy A Kravchuk Panteley I Miklush Polina O Nikiforova Vera V Gordienko Alexander F Popov Boris G Andryukov Department of Infectious Disease Military Medical Academy Named After SM.KirovSaint-Petersburg 194044Russia Department of Admission Federal State Budgetary Institution"North-West District Scientific and Clinical Center Named After LG.Sokolov Federal Medical and Biological Agency"Saint-Petersburg 194291Russia Department of Roentgenology Federal State Budgetary Institution"North-West District Scientific and Clinical Center Named After LG.Sokolov Federal Medical and Biological Agency"Saint-Petersburg 194291Russia Department of Physics Mathematics and InformaticsFSBEI HE IP.Pavlov SPbSMU MOH RussiaSaint-Petersburg 197022Russia 2nd Department of Therapy(Advanced Medical Education) Military Medical Academy Named After SM.KirovSaint-Petersburg 194044Russia School of Medicine Far Eastern Federal UniversityVladivostok 690922Russia

BACKGROUND An important area of effective control of the coronavirus disease 19(COVID-19)pandemic is the study of the pathogenic features of severe acute respiratory syndrome coronavirus 2 infection,including those based on assessing the state of the intestinal microbiota and *** To study the clinical features of the new COVID-19 in patients with mild and moderate severity at the stage of hospitalization,to determine the role of hepatobiliary injury,intestinal permeability disorders,and changes in the qualitative and quantitative composition of the microbiota in the development of systemic inflammation in patients with *** The study was performed in 80 patients with COVID-19,with an average age of 45 years,19 of whom had mild disease,and 61 had moderate disease *** scope of the examination included traditional clinical,laboratory,biochemical,instrumental,and radiation studies,as well as original methods for studying microbiota and intestinal *** The clinical course of COVID-19 was studied,and the clinical and biochemical features,manifestations of systemic inflammation,and intestinal microbiome changes in patients with mild and moderate severity were *** permeability characteristics against the background of COVID-19 were evaluated by measuring levels of proinflammatory cytokines,insulin,faecal calprotectin,and *** This study highlights the role of intestinal permeability and microbiota as the main drivers of gastroenterological manifestations and increased COVID-19 severity.

关键词： Novel coronavirus infection COVID-19 SARS-CoV-2 Zonulin Faecal calprotectin Microbiota

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