This thesis deals with the determination of 14C activity in liquid discharges from the Czech nuclear power plants and with the estimation of their radiological impacts on the vicinity of nuclear power plants. This work summarizes the issue of 14C liquid discharges of several nuclear power plants in the world and Czech nuclear power plants are compared to them. The sewage routs of liquid discharges from control tanks to waste water station are described in this thesis for both power plants - Dukovany and Temelín. Measured values of the 14C activity in liquid discharges from nuclear power plants Temelín and Dukovany are presented in this work. The procedure for calculating the exposure of representative persons as a result of liquid discharge of 14C activity is described in this thesis. The resulting values of annual commited effective dose for each age category of representative persons are presented in this work.

An operator's performance and mental workload when interacting with a complex system, such as the main control room (MCR) of a nuclear power plant (NPP), are major concerns when seeking to accomplish safe and successful operations. The impact of performance on operator workload is one of the most widely researched areas in human factors science with over five hundred workload articles published since the 1960s (Brannick, Salas, & Prince, 1997; Meshkati & Hancock, 2011). Researchers have used specific workload measures across domains to assess the effects of taskload. However, research has not sufficiently assessed the psychometric properties, such as reliability, validity, and sensitivity, which delineates and limits the roles of these measures in workload assessment (Nygren, 1991). As a result, there is no sufficiently effective measure for indicating changes in workload for distinct tasks across multiple domains (Abich, 2013). Abich (2013) was the most recent to systematically test the subjective and objective workload measures for determining the universality and sensitivity of each alone or in combination. This systematic approach assessed taskload changes within three tasks in the context of a military intelligence, surveillance, and reconnaissance (ISR) missions. The purpose for the present experiment was to determine if certain workload measures are sufficiently effective across domains by taking the findings from one domain (military) and testing whether those results hold true in a different domain, that of nuclear. Results showed that only two measures (NASA-TLX frustration and fNIR) were sufficiently effective at indicating workload changes between the three task types in the nuclear domain, but many measures were statistically significant. The results of this research effort combined with the results from Abich (2013) highlight an alarming problem. The ability of subjective and physiological measures to indicate changes in workload varies across tasks (Abich, 2013) and across domain. A single measure is not able to measure the complex construct of workload across different tasks within the same domain or across domains. This research effort highlights the importance of proper methodology. As researchers, we have to identify the appropriate workload measure for all tasks regardless of the domain by investigating the effectiveness of each measure. The findings of the present study suggest that responsible science include evaluating workload measures before use, not relying on prior research or theory. In other words, results indicate that it is only acceptable to use a measure based on prior findings if research has tested that measure on the exact task and manipulations within that specific domain.

[pt] Os princípios de gerenciamento de projetos têm alcançado nos últimos anos um grande interesse por parte das organizações, com objetivos de foco operacional em realizações eficazes dentro do custo, prazo e qualidade planejadas. No entanto, muito pouco se fez para reconhecer a disciplina gerenciamento de projetos como uma das core competencies para a composição do diferencial competitivo na estratégia empresarial selecionada. Esta pesquisa tem como objetivo principal o desenvolvimento de um estudo para averiguar se existe adequação entre os processos da disciplina gerenciamento de projetos e a estratégia da empresa pesquisada. A pesquisa foi desenvolvida por meio de estudo de caso único, para o qual foi selecionada como unidade de análise uma empresa governamental: a Eletrobrás Termonuclear S.A. - Eletronuclear. A coleta de dados foi realizada de acordo com o princípio de triangulação de diferentes métodos (YIN, 2003), e: 1) investigação documental (impressa, telematizada, eletrônica); 2) levantamento de percepções com auxílio de questionário estruturado de pesquisa; 3) levantamento de percepções complementares por meio de entrevistas. As interpretações e análises efetuadas dos dados coletados foram fundamentadas no referencial teórico utilizando-se o modelo genérico-integrativo de Macedo-Soares (2001b). Os resultados evidenciaram algumas inconsistências entre os processos da disciplina gerenciamento de projetos e a estratégia da empresa. Permitiram identificar fatores organizacionais que contribuem e outros que não contribuem para a adequação estratégica de projetos. Na conclusão do trabalho, são compartilhadas lições que a pesquisa focada na Eletronuclear trouxe para outras empresas. / [en] In recent years, organizations have become increasingly interested in the principles of project management in order to enhance the operational effectiveness of their undertakings in terms of planned cost, schedule and quality. However, little has been done in the way of recognizing the discipline of project management as one of the core competencies constituting the competitive differential of the business strategy selected. The main objective of this study is to ascertain whether the processes of the project management discipline fit the strategy of the firm at issue. The study adopted the single case study method, focusing on the government firm Eletrobrás Termonuclear S.A. - Eletronuclear. Data collection was performed in accordance with the method triangulation principle (YIN, 2003), together with 1) documental investigation (printed, telematic, electronic); 2) a perceptions survey using a structured research questionnaire; 3) a complementary perceptions survey through interviews. The data collected was analyzed and interpreted using Macedo-Soares` (2001b) generic integrative model. The results evidenced some inconsistencies between the processes of the project management discipline and the firm´s strategy. They permitted the identification of organizational factors that did or did not contribute to projects´ strategic fit. The study concludes by sharing the lessons for other firms that could be drawn from the Electronuclear case.

The complete design process for a new nuclear power plant concept is costly, long, complicated, and the work is generally split between several specialized groups. These design groups separately do their best to design the portion of the reactor that falls in their expertise according to the design criteria before passing the design to the subsequent design group. Ultimately, the work of each design group is combined, with significant iteration between groups striving to facilitate the integration of each of the heavily interdependent systems. Such complex interaction between experts leads to three significant problems: (1) the issues associated with knowledge management, (2) the lack of design optimization, and (3) the failure to discover the hidden interdependencies between different design parameters that may exist. Some prior work has been accomplished in both developing common frame of reference (CFR) support systems to aid in the design process and applying optimization to nuclear system design.The purpose of this work is to use multi-objective optimization to address the second and third problems above on a small subset of reactor design scenarios. Multi-objective optimization generates several design optima in the form of a Pareto front, which portrays the optimal trade-off between design objectives. As a major part of this work, a system design optimization tool is created, namely the Optimization and Preference Tool for the Improvement of Nuclear Systems (OPTIONS). The OPTIONS tool is initially applied to several individual nuclear systems: the power conversion system (PCS) of the Integral, Inherently Safe Light Water Reactor (I²S-LWR), the Kalina cycle being proposed as the PCS for a LWR, the PERCS (or Passive Endothermic Reaction Cooling System), and the core loop of the Zion plant. Initial sensitivity analysis work and the application of the Non-dominated Sorting Particle Swarm Optimization (NSPSO) method provides a Pareto front of design optima for the PCS of the I²S-LWR, while bringing to light some hidden pressure interdependencies for generating steam using a flash drum. A desire to try many new PCS configurations leads to the development of an original multi-objective optimization method, namely the Mixed-Integer Non-dominated Sorting Genetic Algorithm (MI-NSGA). With this method, the OPTIONS tool provides a novel and improved Pareto front with additional optimal PCS configurations. Then, the simpler NSGA method is used to optimize the Kalina cycle, the PERCS, and the Zion core loop, providing each problem with improved designs and important objective trade-off information. Finally, the OPTIONS tool uses the MI-NSGA method to optimize the integration of three systems (Zion core loop, PERCS, and Rankine cycle PCS) while increasing efficiency, decreasing costs, and improving performance. In addition, the tool is outfitted to receive user preference input to improve the convergence of the optimization to a Pareto front.

No description available.

abstract: This study explores the potential risks associated with the 65 U.S.-based commercial nuclear power plants (NPPs) and the distribution of those risks among the populations of both their respective host communities and of the communities located in outlying areas. First, I examine the relevant environmental justice issues. I start by examining the racial/ethnic composition of the host community populations, as well as the disparities in socio-economic status that exist, if any, between the host communities and communities located in outlying areas. Second, I estimate the statistical associations that exist, if any, between a population's distance from a NPP and several independent variables. I conduct multivariate ordinary least square (OLS) regression analyses and spatial autocorrelation regression (SAR) analyses at the national, regional and individual-NPP levels. Third, I construct a NPP potential risk index (NPP PRI) that defines four discrete risk categories--namely, very high risk, high risk, moderate risk, and low risk. The NPP PRI allows me then to estimate the demographic characteristics of the populations exposed to each so-defined level of risk. Fourth, using the Palo Verde NPP as the subject, I simulate a scenario in which a NPP experiences a core-damage accident. I use the RASCAL 4.3 software to simulate the path of dispersion of the resultant radioactive plume, and to investigate the statistical associations that exist, if any, between the dispersed radioactive plume and the demographic characteristics of the populations located within the plume's footprint. This study utilizes distributive justice theories to understand the distribution of the potential risks associated with NPPs, many of which are unpredictable, irreversible and inescapable. I employ an approach that takes into account multiple stakeholders in order to provide avenues for all parties to express concerns, and to ensure the relevance and actionability of any resulting policy recommendations. / Dissertation/Thesis / Ph.D. Environmental Social Science 2014

This diploma thesis deals with nuclear energetics and its impact to the environment. Present state of the energetics, mainly nuclear energetics, in the Czech Republic is discussed here. Also perspective of nuclear energetics is given. The thesis describes nuclear power plant waste handling and also spent nuclear fuel handling. Nuclear power plant is compared with other sources of electric energy, which are counted to the energetic mix. The author focuses on fossil fuels and also on the renewable energy sources. The amount of produced waste to the unit of produced energy, built up area, safety and economic indicators and other parameters are followed for each source of energy.

在人類社會中，政治代表著一種價值的權威性分配；而公共政策在於顯示政府選擇作 為或不作為，及如何作為的一連串過程；因此，任何有關涉及公共價值分配的決定做 成時，其後必然隱含決策採行的音論根據。所以在決策制定的考慮上，為能期免於來 自執行階段的阻力，與完成目標充分性的（ADEQUANCE） 要求下，其評估（EVALUATE ）的標準（CRITERIAN） 應該是多方面的；因此，林布隆教授（C.E.LINDBLOM）曾言 ：「政策制定的主要特徵在於其複雜性與紊亂性。」由此可見，政策之良善，繫於其 考慮的深度與廣度。但是過去的政策研究基於邏輯實證論的觀點，強調事實面與行為 面的分析，並利用行為科學的數理研究方法以及成本效益分析等技術，以建立政策運 作的效率與效能原則，作為評估公共政策的主要準。然而這樣的立場與觀點，及至１ ９６０年代卅期，遭遇到前所未有的批評與挑戰。於是學者建議在政策評估的標準上 ，應當另闢蹊徑，從價值的層面予以深入的分析與廓清，才不致在狹隘的經濟利益與 目標效能上打轉。因此，在政策論證評估的標準上，不應只單單強調目的的標準（TE LEOLOGICAL-CRITERIA） ，更應該在基本的原則中重視非目的的標準（NONTELEOLOGI CAL-CRITERIA）。也就是政策評估的標準採用，除了要去衡量政策的好壞之外，其在 倫理道德標準上的對與錯更應列為優先考慮。以核能發電為例，在台灣目前政府所面 臨的不單是一個純綷事實資料的政策辯證，它背後所真正隱含著的應該是一種人類對 於科技文明與對後代子孫責任的倫理價值取捨。因此，本文的動機先從檢視４０多年 來有關核能發電的論證依據，並就其政策採行的原因做一整理，而後再就政策的適當 性（APPREPRIATENESS） 論證我們應不應當繼續發展核能發電。

The aim of the thesis was to define the meaning of radiochemical processes which take place in coolant of the primary circuit of the Nuclear Power Plant; and to describe the way of measurement of chemical parameters. The second aim was to define the significance of dissolved hydrogen to compensate for corrosion-threatening corrosion-safe operation of plant and to describe the method of generating hydrogen by ammonia. The third aim was to investigate the time courses of ammonia and hydrogen concentrations within the two production units. The last aim was to investigate unilateral dependence between ammonia and hydrogen concentrations. The first two aims were met by using system analysis of coolant chemical parameters, methods of measuring them, and ongoing radiochemical processes in the coolant. Ammonia and hydrogen were selected for deeper investigation, because of the results of the analysis. H1, H2 and H3 hypotheses have been formulated to meet the other two aims. The H1 hypothesis was used to verify the empirical distribution of ammonia and hydrogen concentration measurements by non-parametric normality testing. Hypothesis H2 investigated the time dependence of ammonia and hydrogen concentrations by regression analysis. In case of verification of H3 hypothesis the method of regression and correlation dependency was used. The verifying of hypothesis has shown that the empirical distribution of the measurement of hydrogen and ammonia concentrations is more closely related to the theoretical normal distribution. Furthermore, it was verified that the linear regression function of the time dependence of ammonia and hydrogen concentration measurements is close to the parallel to the timeline during the fuel campaign. Linear regression and correlation analysis confirmed that the correlation between hydrogen and ammonia concentrations is similar on both blocks and close to strong positive correlation. Verification of required regressive and correlative bending between ammonia and generated hydrogen can be understood as a practical contribution.

The flow distribution in the primary circuit of the pressurized water reactor was studied with experiments and Computational Fluid Dynamics (CFD) simulations. The main focus was on the flow field and mixing in the downcomer of the pressure vessel: how the different factors like the orientation of operating loops, the total loop flow rate and the asymmetry of the loop flow rates affect the outcome. In addition to the flow field studies the overall applicability of CFD methods for primary circuit thermal-hydraulic analysis was evaluated based on the CFD simulations of the mixing experiments of the ROCOM (Rossendorf Coolant Mixing Model) test facility and the mixing experiments of the Paks NPP. The experimental part of the work in work package 3 included series of steady state mixing experiments with the ROCOM test facility and the publication of results of Paks VVER-440 NPP thermal mixing experiments. The ROCOM test facility models a 4-loop KONVOI type reactor. In the steady-state mixing experiments the velocity field in the downcomer was measured using laser Doppler anemometry and the concentration of the tracer solution fed from one loop was measured at the downcomer and at the core inlet plane. The varied parameters were the number and orientation of the operating loops, the total flow rate and the (asymmetric) flow rate of individual loops. The Paks NPP thermal mixing experiments took place during commissioning tests of replaced steam generator safety valves in 1987-1989. It was assumed that in the reactor vessels of Paks VVER-440 NPP equipped with six loops the mixing of the coolant is not ideal. For the realistic determination of the active core inlet temperature field for the transients and accidents associated with different level temperature asymmetry a set of mixing factors were determined. Based on data from the online core monitoring system and a separate mathematical model the mixing factors for loop flows at the core inlet were determined. In the numerical simulation part of the work package 3 the detailed measurements of ROCOM tests were used for the validation of CFD methods for primary circuit studies. The selected steady state mixing experiments were simulated with CFD codes CFX-4, CFX-5 and FLUENT. The velocity field in the downcomer and the mixing of the scalar were compared between CFD simulations and experiments. The CFD simulations of full scale PWR included the simulation of Paks VVER-440 mixing experiment and the simulation of Loviisa VVER-440 downcomer flow field. In the simulations of Paks experiments the experimental and simulated concentration field at the core inlet were compared and conclusions made concerning the results overall and the VVER-440 specific geometry modelling aspects like how to model the perforated elliptic bottom plate and what is the effect of the cold leg bends to the flow field entering to the downcomer. With Loviisa simulations the qualitative comparison was made against the original commissioning experiments but the emphasis was on the CFD method validation and testing. The overall conclusion concerning the CFD modelling of the flow field and mixing in the PWR primary circuit could be that the current computation capacity and physical models also in commercial codes is beginning to be sufficient for simulations giving reliable and useful results for many real primary circuit applications. However the misuse of CFD methods is easy, and the general as well as the nuclear power specific modelling guidelines should be followed when the CFD simulations are made.