In Analogie zu den Systemen für die KKW Saporoshje und Rovno wurden für die drei Blöcke des KKW Südukraine und für den ersten Block des KKW Chmelnitzky technische Systeme zur verbesserten betrieblichen Überwachung eingerichtet. Dazu werden der Aufsichtsbehörde vor Ort und im Krisenzentrum in Kiew einmal pro Minute für jeden Block bis zu 51 sicherheitsrelevante technologische und 16 radiologische Parameter zur Bewertung mittels moderner technischer Ausrüstungen online zur Verfügung gestellt. Die entwickelte Auswertesoftware gestattet die Darstellung der Bewertungsergebnisse in Form von Tabellen, Grafiken und Schemata. Außerdem ermöglicht ein Archivmodus Trendanalysen. Mit der Integration der für die geschützte Warte gelieferten Ausrüstungen in das am Standort des KKW Saporoshje betriebene Fernüberwachungssystem ist es nunmehr möglich, die wesentlichen sicherheitsrelevanten Parameter des gesamten Standortes auch bei außergewöhnlichen Ereignissen mit Hilfe moderner Technik zu erfassen und zu bewerten.

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In Analogie zu den Systemen für die KKW Saporoshje und Rovno wurden für die drei Blöcke des KKW Südukraine und für den ersten Block des KKW Chmelnitzky technische Systeme zur verbesserten betrieblichen Überwachung eingerichtet. Dazu werden der Aufsichtsbehörde vor Ort und im Krisenzentrum in Kiew einmal pro Minute für jeden Block bis zu 51 sicherheitsrelevante technologische und 16 radiologische Parameter zur Bewertung mittels moderner technischer Ausrüstungen online zur Verfügung gestellt. Die entwickelte Auswertesoftware gestattet die Darstellung der Bewertungsergebnisse in Form von Tabellen, Grafiken und Schemata. Außerdem ermöglicht ein Archivmodus Trendanalysen. Mit der Integration der für die geschützte Warte gelieferten Ausrüstungen in das am Standort des KKW Saporoshje betriebene Fernüberwachungssystem ist es nunmehr möglich, die wesentlichen sicherheitsrelevanten Parameter des gesamten Standortes auch bei außergewöhnlichen Ereignissen mit Hilfe moderner Technik zu erfassen und zu bewerten.

Management decisions in complex industrial facilities usually consider both the economic and environmental aspects of the plant's performance. For nuclear power plants (NPPs), safety is also a very substantial issue. The objectives of this dissertation are to develop and demonstrate a novel useful conceptual model that could be used to allocate maintenance funds for a nuclear power plant in such a way as to meet all specified safety requirements and objectives, while achieving a high degree of economic performance. The model is based on the general theory that the reliability of a plant at any time is a function of its initial reliability and the maintenance history of the individual plant components (Smith, 1997). Such a model can assist in evaluating strategic management decisions regarding allocation of funds for nuclear power plant maintenance. It could be used as a simulation tool; various scenarios could be studied to answer "what if" questions. Simulations of this type will allow a better understanding of the relationship between maintenance, economic performance, and safety, and consequently will lead to better decision making. The novelty of this model is tied to the intimate relationship that it develops between maintenance activities at a nuclear plant, and their relationship to prescribed safety requirements and to the economic performance of that plant.

Management decisions in complex industrial facilities usually consider both the economic and environmental aspects of the plant's performance. For nuclear power plants (NPPs), safety is also a very substantial issue. The objectives of this dissertation are to develop and demonstrate a novel useful conceptual model that could be used to allocate maintenance funds for a nuclear power plant in such a way as to meet all specified safety requirements and objectives, while achieving a high degree of economic performance. The model is based on the general theory that the reliability of a plant at any time is a function of its initial reliability and the maintenance history of the individual plant components (Smith, 1997). Such a model can assist in evaluating strategic management decisions regarding allocation of funds for nuclear power plant maintenance. It could be used as a simulation tool; various scenarios could be studied to answer "what if" questions. Simulations of this type will allow a better understanding of the relationship between maintenance, economic performance, and safety, and consequently will lead to better decision making. The novelty of this model is tied to the intimate relationship that it develops between maintenance activities at a nuclear plant, and their relationship to prescribed safety requirements and to the economic performance of that plant.

IN ENGLISH Atomic Law deals with the modern phenomenon of atomic energy and is constantly evolving. This thesis deals with the Czech atomic law. Given the seriousness of the issues in nuclear safety and radiation treatment is Czech law very consistent with the international and European level, as this work takes into account and includes. Due to a number of technical terms , which are necessary to work with, some of the terms are defined in the introduction of this thesis. These are the most common and very basic concepts, such as: "nuclear energy", "ionizing and non-ionizing - radiation"and also "atomic law". The thesis also covers some aspects of atomic energy in terms of the potential benefits and risks that come with its use entails. Furthermore, it pays attention to the legislation itself. Firstly from the perspective of international law and European Union law, which have a major influence on national legislation . Afterwards some of the basic regulatory objectives, nuclear law and most general and special legal principles applied in this area are described. The following is a brief overview of nuclear law in the Czech Republic together with Chapter dealing with in the activities and organizations of the State Office for nuclear safety , as the central authority in the field of peaceful use of...

All of us make more or less important decisions during our entire lives, in private and professional arenas. Some decisions have consequences for an individual or organization in the short term, others have long lasting consequences. This thesis concerns studies of decision processes and structures involved indecision-making with medium to long-term consequences for an organization or individual. Study I and II focus decision-making theory and judgments in procurement. Study III concerns real-life, individual career decision-making. Study I used a laboratory context for an investigation of willingness to pay (WP) for the creation of a procurement offer. Study II investigated organizational decision processes and structures of procurement of large projects in a nuclear power plant organization. Study III investigated the decision process used to make a choice between two professional training programs leading to psychotherapist certification. Study I found, that participants used a multiplicative combination of probability and profit when judging WP for the creation of a bid. Scales of subjective probability had smaller ranges than objective probability. In this context, participants were more sensitive to variation in monetary value than to probability. In Study, II it was possible to describe the procurement process in a framework of information search and decision theory. A Multi Attribute Utility Theory-inspired model was used by the staff, in the evaluations of procurement alternatives. Both compensatory (e.g. negative aspects can be compensated by positive aspects) and non-compensatory (particular “pass” levels of attributes have to be exceeded for acceptance of a choice alternative) decision rules were used. In study III it was found that a development and extension of Differentiation and Consolidation theory described individual reasons pro and con alternatives before and after the choice of a professional training program. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 1: Submitted. </p>

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At the beginning of 2011, the former Forschungszentrum Dresden-Rossendorf (FZD) was fully integrated into the Helmholtz Association, as Helmholtz-Zentrum Dresden-Rossendorf (HZDR). Therefore, the present Annual Report 2010 of the Institute of Radiochemistry (IRC) is published as the first HZDR-Report. The Institute of Radiochemistry is one of the six Research Institutes of this centre. IRC contributes to the research program “Nuclear Safety Research” in the “Research Field of Energy” and performs basic and applied research in radiochemistry and radioecology. Motivation and background of our research are environmental processes relevant for the installation of nuclear waste repositories, for remediation of uranium mining and milling sites, and for radioactive contaminations caused by nuclear accidents and fallout. Because of their high radiotoxicity and long half-life the actinides are of special interest.

Ce travail propose une étude expérimentale de l'ébullition en masse dans une structure poreuse modèle. L'objectif est d'approfondir la compréhension des transferts de chaleur dans un écoulement diphasique avec changement de phase liquide-vapeur en milieu poreux, en liaison avec la problématique de la gestion des accidents graves dans les réacteurs nucléaires. A la suite d'un dysfonctionnement sur le circuit de refroidissement d'un réacteur nucléaire, l'augmentation de la température au sein du cœur provoque l'effondrement des tubes contenant le combustible. Il en résulte la formation d'un lit de débris chaud, assimilable à un milieu poreux dégageant une puissance thermique importante, qui peut être refroidi efficacement par renoyage avec de l'eau. Cela engendre des mécanismes d'ébullition intenses qu'il convient de modéliser proprement pour estimer les chances de succès du renoyage. Notre étude vise à caractériser les échanges de chaleur à l'échelle du pore en fonction des caractéristiques de l'écoulement local. Une partie importante du travail a été consacrée à la mise au point du dispositif expérimental. Le cœur du dispositif est un milieu poreux bidimensionnel formé de cylindres disposés aléatoirement entre deux plaques de céramique. Chaque cylindre est une sonde à résistance de platine, utilisée non seulement pour fournir la puissance thermique désirée mais aussi pour mesurer la température de l'élément : chaque élément chauffant est contrôlé individuellement ou en groupe à l'aide d'un système d'asservissement temps réel. La plaque supérieure étant transparente, la distribution des phases au sein du poreux est obtenue par visualisation haute vitesse. L'acquisition d'images et les mesures thermiques permettent de caractériser l'échange de chaleur effectif local en fonction du régime d'ébullition. Deux configurations principales ont été étudiées. Dans la première, le milieu est initialement saturé en liquide et chauffé jusqu'à l'apparition de la vapeur et l'obtention de différents régimes d'ébullition. Ceci a notamment permis d'établir des courbes de Nukiyama en milieu confiné. Dans la seconde, dite de renoyage, le liquide est injecté dans le milieu sec et surchauffé initialement. Ceci a permis de caractériser la dynamique du renoyage et de visualiser les régimes d'écoulement rencontrés. Les résultats sont discutés en relation avec le modèle macroscopique à non-équilibre thermique local actuellement le plus avancé pour l'étude de ces différentes situations d'ébullition. / This manuscript presents a pore-scale experimental study of convective boiling heat transfer in a two-dimensional porous medium. The purpose is to deepen the understanding of thermohydraulics of porous media saturated with multiple fluid phases, in order to enhance management of severe accidents in nuclear reactors. Indeed, following a long-lasting failure in the cooling system of a pressurized water reactor (PWR) or a boiling water reactor (BWR) and despite the lowering of the control rods that stops the fission reaction, residual power due to radioactive decay keeps heating up the core. This induces water evaporation, which leads to the drying and degradation of the fuel rods. The resulting hot debris bed, comparable to a porous heat-generating medium, can be cooled down by reflooding, provided a water source is available. This process involves intense boiling mechanisms that must be modelled properly. The experimental study of boiling in porous media presented in this thesis focuses on the influence of different pore-scale boiling regimes on local heat transfer. The experimental setup is a model porous medium made of a bundle of heating cylinders randomly placed between two ceramic plates, one of which is transparent. Each cylinder is a resistance temperature detector (RTD) used to give temperature measurements as well as heat generation. Thermal measurements and high-speed image acquisition allow the effective heat exchanges to be characterized according to the observed local boiling regimes. This provides precious indications precious indications for the type of correlations used in the non-equilibrium macroscopic model used to model reflooding process.