Peculiarities of development of the generalized Faraday effect for spherical and ellipsoidal reservoirs

Класична задача Фарадея про параметричні коливання рідини у циліндричному резервуарі, що здійснює гармонічні коливання строго у вертикальному напрямку. Узагальнення класичної задачі Фарадея здійснюється в таких напрямках. Перше, рух резервуара у вертикальному напрямку розглядається не за заданим законом, а як результат дії гармонічної за часом вертикальної сили. Друге, оскільки відбувається поперечний (горизонтальний) рух рідини, допускається відповідний горизонтальний рух резервуару. Третє, розглядається резервуар нециліндричної форми. Четверте, задача розглядається в рамках нелінійної моделі сумісного руху складових системи, що, зокрема, проявляється у зміні власних частот. Аналізуються особливості поведінки системи

Radiation source rate estimation through data assimilation of gamma dose rate measurements for operational nuclear emergency response systems

This paper presents an evaluation of an innovative data assimilation method that has been recently developed in NCSR Demokritos for estimating an unknown emission rate of radionuclides in the atmosphere, with real-scale experimental data. The efficient algorithm is based on the assimilation of gamma dose rate measured data in the Lagrangian atmospheric dispersion model DIPCOT and uses variational principles. The DIPCOT model is used in the framework of the nuclear emergency response system (ERS) RODOS. The evaluation is performed by computational simulations of dispersion of Ar-41 that was emitted routinely by the Australian Nuclear Science and Technology Organisation’s (ANSTO) previous research reactor, HIFAR, located in Sydney, Australia. In this paper the algorithm is evaluated against a more complicated Radiation source rate estimation through data assimilation 387 case than the others used in previous studies: There was only one monitoring station available each day and the site topography is characterised as moderately complex. Overall the estimated release rate approaches the real one to a very satisfactory degree as revealed by the statistical indicators of errors. © 2012 Inderscience Enterprises Ltd

Software to convert NCEP-grib1/grib2 files to HIRLAM-GRIB format to enable running MATCH

This document describes the software developed to convert the numerical weather prediction data calculated by NCEP/GFS model and provided in GRIB format to HIRLAM-GRIB format which is used by the far-range model of atmospheric transport MATCH of the RODOS system. The software also enables possibility to reverse u- and v-velocity components for running backward calculations. When using this software please cite the following paper: Kovalets I. V., Robertson L., Persson C., Didkivska S.N., Ievdin I.A. Trybushnyi D. (2014) Calculation of the far range atmospheric transport of radionuclides after the Fukushima accident with the atmospheric dispersion model MATCH of the JRODOS system // Int. J. of Environment and Pollution. – 2014. – Vol. 54, No 2/3/4. – P. 101-109, doi: 10.1504/IJEP.2014.06511

Advanced method for source term estimation and status of its integration in JRODOS

In this work we present an automated source inversion algorithm suitable for usage in the real-time online emergency response system JRODOS in which measurements of gamma dose rates and other quantities taken at a wide range of distances from the Nuclear Power Plant are used to provide estimates of the time-dependent emission rates of different nuclides