[en] An important aspect of an Earth Systems Science Prediction Systems (ESSPS) is to describe and predict the behavior of contaminants in different environmental compartments following severe accidents at chemical and nuclear installations. Such an ESSPS could be designed as a platform allowing to integrate models describing atmospheric, hydrological, oceanographic processes, physical-chemical transformation of the pollutants in the environment, contamination of food chain, and finally the overall exposure of the population with harmful substances. Such a chain of connected simulation models needed to describe the consequences of severe accidents in the different phases of an emergency should use different input data ranging from real-time online meteorological to long-term numerical weather prediction or ocean data. One example of an ESSPS is the Decision Support Systems JRODOS for off-site emergency management after nuclear emergencies. It integrates many different simulation models, real-time monitoring, regional GIS information, source term databases, and geospatial data for population and environmental characteristics. The development of the system started in 1992 supported by European Commission’s RTD Framework programs. Attracting more and more end users, the technical basis of of the system had to be considerably improved. For this, Java has been selected as a high level software language suitable for development of distributed cross-platform enterprise quality applications. From the other hand, a great deal of scientific computational software is available only as C/C++/FORTRAN packages. Moreover, it is a common scenario when some outputs of model A should act as inputs of model B, but the two models do not share common exchange containers and/or are written in different programming languages. To combine the flexibility of Java language and the speed and availability of scientific codes, and to be able to connect different computational codes into one chain of models, the notion of distributed wrapper objects (DWO) has been introduced. DWO provides logical, visual and technical means for the integration of computational models into the core of the system system, even if models and the system use different programming languages. The DWO technology allows various levels of interactivity including pull- and push driven chains, user interaction support, and sub-models calls. All the DWO data exchange is realized in memory and does not include IO disk operations, thus eliminating redundant reader/writer code and minimizing slow disk access. These features introduce more stability and performance of an ESSPS that is used for decision support. The current status of the DWO realization in JRODOS is presented focusing on the added value compared to traditional integration of different simulation models into one system.

[en] Full text: The European decision support system for nuclear and radiological emergencies RODOS includes a set of numerical models simulating the transport of radionuclides in the environment, estimating potential doses to the public and simulating and evaluating the efficiency of countermeasures. The re-engineering of the RODOS system using the Java technology has started recently which will allow to apply the new system called JRODOS on nearly any computational platform running Java virtual machine. Modern software development approaches were used for the JRODOS system architecture and implementation: distributed system design (client, management server, computational server), geo-database utilization, plug-in model structure and OpenMI-like compatibility to support seamless model inter-connection. Stable open source components such as an ORM solution (Hibernate), an OpenGIS component (Geotools) and a charting/reporting component (JFree, Pentaho) were utilized to optimize the development effort and allow a fast completion of the project. The architecture of the system is presented and illustrated for the atmospheric dispersion module ALSMC (Atmospheric Local Scale Model Chain) performing calculations of atmospheric pollution transport and the corresponding acute doses and dose rates. The example application is based on a synthetic scenario of a release from a nuclear power plant located in Europe. (author)

[en] The decision support system for offsite nuclear emergency management RODOS (Real-time on-line decision support), developed under several EC RTD Framework Programs, contains many models related to support decision making in case of a nuclear or radiological emergency. Based on the request of the end users, it was re-engineered based on the JAVA technology and further named JRODOS. The consequences of the Fukushima Daiichi Nuclear Power Plant accident clearly demonstrated the importance of modeling tools predicting the radionuclide transport in marine and freshwater environment and assessing the doses to the public via the aquatic food chain to improve decision making in general. As a consequence, such an activity was launched as part of the European project PREPARE aiming to integrate the 3-dimensional model THREETOX for the radionuclide transport in coastal waters, estuaries, deep lakes, and reservoirs into hydrological model chain of JRODOS - JHDM (JRODOS Hydrological Dispersion Module). So far JHDM contains several aquatic radionuclide transport models describing the sequence of the processes 'atmospheric fallout to watershed' - 'radionuclide inflow to a river net' - 'radionuclide transport in river' - 'doses via aquatic pathways'. The implementation of the THREETOX model into this chain by developing also a user friendly interface will extend the applicability of JRODOS to deep fresh water bodies and marine coastal waters. This paper describes the assessment capabilities of this advanced model chain for two examples of the JRODOS implementation in Ukraine. JRODOS is installed in the emergency centers for two Ukrainian Nuclear Power Plants (NPP) - Zaporizzhya NPP (ZNPP) and Rivne NPP (RNPP). The different models of the JHDM were customized for these NPPs taking into account the characteristics of the water bodies in the surroundings of the NPPs. For the RNPP, located at the bank of the Sozh River which is a tributary of the Pripyat River, the modeling chain includes 'atmospheric fallout to watershed' - 'radionuclide inflow to river net using the RETRACE -R model' - 'radionuclide transport in river using the 1D model RIVTOX' - 'doses via aquatic pathways using the FDMA model', For the ZNPP, located close to the large (18 cub.km) Kakhovka Reservoir, the modeling chain consists of 'atmospheric fallout to reservoirs water surface' - 'radionuclide transport in the reservoir applying the 3D model THREETOX' - ' radionuclide transport in the Dnieper river downstream of the Kakhovka Reservoir applying the 1D model RIVTOX'- 'doses via aquatic pathways applying the FDMA model'. The above mentioned model chains have been tested for different accidental release scenarios for both NPPs. These dose assessments for potential major release accidents are extremely important to improve emergency preparedness and planning. Document available in abstract form only. (authors)

No abstract available