[en] Software of asymmetric stationary simulation for the Industrial Heavy Water Plant (PIAP) was developed, based on an existing symmetric simulator (Brigitte 2.0).This software allows to turn off some of the isotopic enrichment twin units present in the plant and to simulate them asymmetrically, in other words, with different selection of parameters between twins.Other incorporations were done, such as passing flows between units and entering flows in strategic points of the plant.The iterative system in which the symmetric simulator is based was insufficient to develop the asymmetric simulator, so the system was modeled according to an implicit scheme for the units that form the simulator.This type of resolution resulted in a simulator that supports a big range of boundary conditions and internal parameters.Moreover, the time of calculus is short (∼3 minutes), making it actually useful.The asymmetric simulator is at the PIAP now, for its study and validation. It shows expected tendencies and results according to the symmetric simulator already validated

[en] An European task force on integrated tokamak modelling has been activated with the long-term aim of providing the EU with a set of codes necessary for preparing and analysing future ITER discharges, with the highest degree of flexibility and reliability. The task force is structured under seven projects establishing the foundations of the fusion simulators. (author)

[en] This paper presents the status and training possibilities on Krsko NPP Multi-Functional Simulator (NEK-MFS). Since spring 1997 it serves as a training facility in Nuclear Training Center. During first year of operation the simulator NEK-MFS was found to be a very useful Krsko NPP specific tool which is capable to support both the initial operator training program and licensed operator retraining activities.(author)

[en] The Refining and Petrochemical Process Simulator - PETROX, developed by PETROBRAS/CENPES in partnership with CHEMTECH, has been improved continuously to cover a variety of applications, from new thermodynamic models for specific processes, to sophisticated algorithms of equipment and process optimization. The most recent available implementation in PETROX is the graphic interface for Windows 95/98 and N T platforms, that intends to minimize the learning time in the use of the simulator and maximize the productivity of several teams that already use it in the tasks of basic design, plant operation, debottlenecking and process optimization, or as a virtual analyzer in inference systems. This work describes the main characteristics of the graphic interface of PETROX emphasizing its ingenious solution to solve modeling and visualization of classic simulation data problems. (author)

[en] NPP Krsko (NEK) will, as a part of the Modernization plan, obtain also Krsko Full Scope Simulator (KFSS). Contract has been awarded to CAE Electronics for the design, construction and integration. KFSS will support in real time, the training for the complete range of operation, which can be performed from the main control room and some selected plant areas (remote shutdown panels, etc). Based on the lessons learned on development of NPP Krsko Basic Principle Simulator we decided for active approach. That means that NPP Krsko personnel will be heavily involved into all phases of KFSS development and testing. Since NPP Krsko is going to replace the existing steam generators, raise the nominal power and perform necessary modifications to support the power uprate, it was decided that the development of the KFSS will be conducted in two steps: 1. Development of the models as well as all the hardware interface in the MCR for the existing plant Cycle 15 and then, 2. Models and hardware will be modified, added or replaced as needed to take into account the steam generator replacement and plant uprate projects. In spite of the fact that the simulator will be used for the training of the plant operators for the uprated conditions and with new steam generators, the upper described approach was selected since we want to be sure that the models will at the beginning adequately simulate the existing plant. For the existing conditions we have available reference data for different plant conditions, as well as data for different plant transients. By verifying that simulator will be able adequately simulate the existing conditions the level of confidence for the uprated simulator will be much higher. This is of special importance since it will support initial training for modernized plant conditions. In this paper the plan for verification and qualification of KFSS as well as the amount of the work needed on NPP Krsko side to develop the test acceptance criteria will be presented.(author)

[en] Laboratory receiver operating characteristic (ROC) studies, that are often used to evaluate medical imaging systems, differ from ‘live’ clinical interpretations in several respects which could compromise their clinical relevance. The aim was to develop methodology for quantifying the clinical relevance of a laboratory ROC study. A simulator was developed to generate ROC ratings data and binary clinical interpretations classified as correct or incorrect for a common set of images interpreted under clinical and laboratory conditions. The area under the trapezoidal ROC curve (AUC) was used as the laboratory figure-of-merit and the fraction of correct clinical decisions as the clinical figure-of-merit. Conventional agreement measures (Pearson, Spearman, Kendall and kappa) between the bootstrap-induced fluctuations of the two figures of merit were estimated. A jackknife pseudovalue transformation applied to the figures of merit was also investigated as a way to capture agreement existing at the individual image level that could be lost at the figure-of-merit level. It is shown that the pseudovalues define a relevance-ROC curve. The area under this curve (rAUC) measures the ability of the laboratory figure-of-merit-based pseudovalues to correctly classify incorrect versus correct clinical interpretations. Therefore, rAUC is a measure of the clinical relevance of an ROC study. The conventional measures and rAUC were compared under varying simulator conditions. It was found that design details of the ROC study, namely the number of bins, the difficulty level of the images, the ratio of disease-present to disease-absent images and the unavoidable difference between laboratory and clinical performance levels, can lead to serious underestimation of the agreement as indicated by conventional agreement measures, even for perfectly correlated data, while rAUC showed high agreement and was relatively immune to these details. At the same time rAUC was sensitive to factors such as intrinsic correlation between the laboratory and clinical decision variables and differences in reporting thresholds that are expected to influence agreement both at the individual image level and at the figure-of-merit level. Suggestions are made for how to conduct relevance-ROC studies aimed at assessing agreement between laboratory and clinical interpretations. The method could be used to evaluate the clinical relevance of alternative scalar figures of merit, such as the sensitivity at a predifined specificity. (paper)

[en] Current techniques for creating clouds in games and other real time applications produce static, homogenous clouds. These clouds, while viable for real time applications, do not exhibit an organic feel that clouds in nature exhibit. These clouds, when viewed over a time period, were able to deform their initial shape and move in a more organic and dynamic way. With cloud shape technology we should be able in the future to extend to create even more cloud shapes in real time with more forces. Clouds are an essential part of any computer model of a landscape or an animation of an outdoor scene. A realistic animation of clouds is also important for creating scenes for flight simulators, movies, games, and other. Our goal was to create a realistic animation of clouds

[en] The book contains the papers presented at the symposium. The papers are classified according to the following topics: 1. hardware tools; 2. simulation-software-tools; 3. plant analyser; 4. reactor core; 5. nuclear waste. All papers are separately indexed in the database. (orig./HP) With 107 figs

[en] During the assessment of the nuclear safety level in Slovenia the SNSA (Slovenian Nuclear Safety Administration) found a need to gain a software support for analyzing the transients of the Krsko Nuclear Power Plant. Combining the RELAP5 code with graphical interface NPA (Nuclear Plant Analyzer) management staff saw an opportunity to have a powerful instrument for analyses and calculations on a user friendly basis and to get familiar with RELAP5 input deck without extra costs. At the beginning the project started with first phase, where Jozef Stefan Institute - OR4 formed a basic scope of the work and prepared the demo version of the SBLOCA on the basis of RELAP5/Mod3.1code input deck. Tractebel was chosen as a supplier of the project's second phase on the base of public bid. In 1996 the work started with translation of the input model from version Mod2.5 to Mod3.2 with standard routines and small final corrections. After this phase of the project a user of the Krsko NPP Analyzer can run accidents as SBLOCA, Main Steam Line Break, Feedwater Line Break, SGTR, and many other transients activating and combining interactive commands, starting from a full power operation. The third phase is planed. The SNSA has plans to improve the model of the Krsko NPP for a better simulation of core phenomena and to have detailed models of safety and auxiliary systems for increasing the number of possible transients and failures. The Critical Safety Function window will be created as a special mask. The analyzer will be used for education of employees and external experts, who are engaged in case of an emergency, to get familiar with the NPP systems and their operation. During the assessment of the nuclear safety level in Slovenia the SNSA (Slovenian Nuclear Safety Administration) found a need to gain a software support for analyzing the transients of the Krsko Nuclear Power Plant. Combining the RELAP5 code with graphical interface NPA (Nuclear Plant Analyzer) management staff saw an opportunity to have a powerful instrument for analyses and calculations on a user friendly basis and to get familiar with RELAP5 input deck without extra costs. At the beginning the project started with first phase, where Jozef Stefan Institute - OR4 formed a basic scope of the work and prepared the demo version of the SBLOCA on the basis of RELAP5/Mod3.1code input deck. Tractebel was chosen as a supplier of the project's second phase on the base of public bid. In 1996 the work started with translation of the input model from version Mod2.5 to Mod3.2 with standard routines and small final corrections. After this phase of the project a user of the Krsko NPP Analyzer can run accidents as SBLOCA, Main Steam Line Break, Feedwater Line Break, SGTR, and many other transients activating and combining interactive commands, starting from a full power operation. The third phase is planed. The SNSA has plans to improve the model of the Krsko NPP for a better simulation of core phenomena and to have detailed models of safety and auxiliary systems for increasing the number of possible transients and failures. The Critical Safety Function window will be created as a special mask. The analyzer will be used for education of employees and external experts, who are engaged in case of an emergency, to get familiar with the NPP systems and their operation. (author)

[en] The paper presents the results of the study conducted to support planned modernization of the South Ukraine nuclear power plant. The objective of the analysis has been to develop the automated emergency control algorithm for primary to secondary LOCA accident for SUNPP WWER-1000 safety upgrading. According to the analyses performed in the framework of safety assesment report, given accident is the most complex for control and has the largest contribution into the core damage frequency value. This is because of initial event diagnostics is difficult, emergency control is complicated for personnel, time available for decision making and actions performing is limited with coolant inventory for make-up, probability of steam dump valves on affected steam generator non-closing after opening is high, and as a consequence containment bypass, irretrievable loss of coolant and radioactive materials release into the environment are possible. Unit design modifications are directed on expansion of safety systems capabilities to overcome given accident and to facilitate the personnel actions on emergency control. Safety systems modification according to developed algorithm will allow to simplify accident control by personnel and enable to control the ECCS discharge limiting pressure below the affected steam generator steam dump valve opening pressure, and decrease the probability of the containment bypass sequences. The analysis of the primary-to-secondary LOCA thermal-hydraulics has been conducted with RELAP5/Mod 3.2, and involved development of the dedicated analytical model, calculations of various plant response accident scenarios, conducting of plant personnel intervention analyses using full-scale simulator, development and justification of the emergency control algorithm aimed on the minimization of negative consequences of the primary-to-secondary LOCA (Authors)