26 research outputs found

    About the Perturbing Factors Influence in the Spacecraft Motion Simulation Model

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    Abstract The new simulation model of the spacecraft's center of mass motion with taking into account of gravitational potentials of the Earth, the Moon and the Sun is presented in this paper. The simulation model was created on the basis of analysis of the present mathematical models of gravitational potentials of the Earth, the Moon and the Sun and different methods of numeral calculation. Influence of the Earth's atmosphere, which causes the spacecraft motion deceleration, was taken into account. By means of the created simulation model the analysis of the environment perturbation factors influencing on the spacecraft motion trajectory was carried out. It has been revealed that deviation of the calculated orbit from the given one depends on orbit height, and this dependence has been defined. The estimation of relative influence of the moments of various forces on the mass center motion was carried out

    Spatial variations in the Caspian Sea wave climate in 2002-2013 from satellite altimetry

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    The core properties of the wave climate and its changes in the Caspian Sea are established in terms of the annual mean significant wave height and its regional changes in 2002-2013 based on the outcome of the satellite altimetry mission JASON-1. Remotely estimated wave heights are validated against properties of the empirical distribution of instrumentally measured wave heights in the southern Caspian Sea and monthly averages of visually observed wave heights at three locations. A correction for systematic differences leads to very good correspondence between monthly averaged in situ and satellite data with a typical root mean square difference of 0.06 m. The average significant wave height in the Caspian Sea is 0.5-0.7 m in the northern basin of the sea, around 1.2 m in large parts of the central and southern basins and reaches up to 1.8 m in the northern segment of the central basin. The basin-wide average wave intensity varied insignificantly in the range of 1.02-1.14 m in 2002-2013. These estimates overestimate the wave heights by about 30% because low wave conditions are ignored. Substantial and statistically significant changes in the wave height occurred in certain areas. The wave height decreased by 0.019 +- 0.007 m/yr in the eastern segment of the central basin and by 0.04 +- 0.04 m/yr in the western segment of the southern basin. These changes can be explained by an increase in the frequency of westerly winds at the expence of southerly winds. Both basin-wide and regional extreme wave heights exhibit large interannual variations but do not show any significant trend. The patterns of changes in mean and extreme wave height are different. The average wave height has increased while the extreme wave height has decreased in the eastern segment of the southern basin.Comment: 16 pages, 10 figure

    SMES DEVELOPMENT AND CORRUPTION: CASE OF KAZAKHSTAN

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    The article presents a study of the corruption perception and the involvement of SMEs in corruption practices. The main goal of the paper is to provide an analysis of corruption perception of the SMEs representatives, its parts and research methodology to provide an adequate picture and analysis of corruption of the Kazakhstan. For obtaining a comparative picture, we interviewed 500 representatives of SMEs and 500 civil servants. We used a mass survey (face-to-face) method. The results show that the presence of “gap” between perception of corruption and degree of the respondents’ involvement in corrupt practices. The respondents believe that corruption is widespread, but they themselves were rarely involved in corrupt practices. The key message is that the SMEs representatives consider this problem to be acute, but they are not ready to talk about their own experience in this regard

    COVID-19 vaccination in patients with heart failure: a position paper of the Heart Failure Association of the European Society of Cardiology

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    Patients with heart failure (HF) who contract SARS-CoV-2 infection are at a higher risk of cardiovascular and non-cardiovascular morbidity and mortality. Regardless of therapeutic attempts in COVID-19, vaccination remains the most promising global approach at present for controlling this disease. There are several concerns and misconceptions regarding the clinical indications, optimal mode of delivery, safety and efficacy of COVID-19 vaccines for patients with HF. This document provides guidance to all healthcare professionals regarding the implementation of a COVID-19 vaccination scheme in patients with HF. COVID-19 vaccination is indicated in all patients with HF, including those who are immunocompromised (e.g. after heart transplantation receiving immunosuppressive therapy) and with frailty syndrome. It is preferable to vaccinate against COVID-19 patients with HF in an optimal clinical state, which would include clinical stability, adequate hydration and nutrition, optimized treatment of HF and other comorbidities (including iron deficiency), but corrective measures should not be allowed to delay vaccination. Patients with HF who have been vaccinated against COVID-19 need to continue precautionary measures, including the use of facemasks, hand hygiene and social distancing. Knowledge on strategies preventing SARS-CoV-2 infection (including the COVID-19 vaccination) should be included in the comprehensive educational programmes delivered to patients with HF. This article is protected by copyright. All rights reserved
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