Spyros Andronopoulos

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One of the key problems in coping with deliberate or accidental atmospheric releases is the ability to reliably predict the individual exposure during the event. Furthermore, for the implementation of countermeasures, it is essential to predict the maximum expected dosage and the exposure time within which the dosage exceeds certain health limits. Current(More)
The paper presents the development of a model for the calculation of the gamma radiation dose rate from a cloud or plume of radionuclides. The model has been implemented in the Lagrangian puff dispersion model DIPCOT which is used in the framework of the RODOS system for nuclear emergency management. The basic characteristics of the model are its speed of(More)
This paper presents an efficient algorithm for estimating the unknown emission rate of radionuclides in the atmosphere following a nuclear accident. The algorithm is based on assimilation of gamma dose rate measured data in a Lagrangian atmospheric dispersion model. Such models are used in the framework of nuclear emergency response systems (ERSs). It is(More)
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(More)
Is atmospheric dispersion forecasting an important asset of the early-phase nuclear emergency response management? Is there a 'perfect atmospheric dispersion model'? Is there a way to make the results of dispersion models more reliable and trustworthy? While seeking to answer these questions the multi-model ensemble dispersion forecast system ENSEMBLE will(More)
In previous work [Kovalets, I., Andronopoulos, S., Bartzis, J.G., Gounaris, N., Kushchan, A., 2004. Introduction of data assimilation procedures in the meteorological pre-processor of atmospheric dispersion models used in emergency response systems. Atmospheric Environment 38, 457–467.] the authors have developed data assimilation (DA) procedures and(More)
INTRODUCTION The “Hanford Scenario” refers to an acute accidental release of radioactive I from the stack of the Hanford (USA) Purex Chemical Separations Plant that occurred between 2 and 5 of September 1963 (BIOMASS, 1999). From the environmental impact point of view it is a very interesting case study for the evaluation of computational systems that(More)
The management and analysis of large-scale datasets – described with the term Big Data – involves the three classic dimensions volume, velocity and variety. While the former two are well supported by a plethora of software components, the variety dimension is still rather neglected. We present the BDE platform – an easy-to-deploy, easy-to-use and adaptable(More)
The real-time applicability of the ADREA-I prognostic mesoscale meteorological model was enhanced by applying the preconditioned BiCGSTAB method for the numerical solution of the pressure equation in combination with increasing the magnitude of the time steps up to the values allowed by the Courant number. The ILU, MILU ILUT and ILUM preconditioning methods(More)