Problema – Lietuvoje nėra sukurtos laisvojo aerostato pilotų rengimo pagal Pasaulinės aviacijos federacijos reikalavimus ir Europos Komisijos reglamentą. Tyrimai Lietuvos oro balionų sporto organizacijose parodė, kad būtina sukurti tobulesnį oro pilotų rengimo modelį, kuris atitiktų Pasaulinės aviacijos federacijos reikalavimus ir Europos Komisijos reglamentą; būtina tobulinti oro pilotų (pradedant moksleiviais ir baigiant pageidaujančiais pagyvenusiais žmonėmis) rengimo sistemą bei didinant šio sporto masiškumą plėsti Lietuvos oreivių draugijos klubų ir kitų padalinių steigimo geografiją. Darbo tikslas – sukurti Lietuvos laisvojo aerostato pilotų rengimo modelį. Objektas – Lietuvos laisvojo aerostato licencijuotų pilotų rengimo modelis Darbo uždaviniai: 1. Apžvelgti specialistų kompetencijų ir laisvojo aerostato licencijuotų pilotų rengimo teorinius aspektus. 2. Sukurti laisvojo aerostato piloto kompetencijų teorinį modelį. 3. Parengti tyrimo metodiką empiriniam tyrimui ir atlikti anketavimą Lietuvos oro balionų sporto organizacijose. 4. Pagrįsti laisvojo aerostato licencijuotų pilotų rengimo modelį. Tyrimo metodai: mokslinės literatūros šaltinių analizė, anketinė apklausa bei statistinė duomenų analizė. Darbas susideda iš trijų dalių. Pirmoje pateikta literatūroje paskelbtų teorinių aspektų apie kompetencijas ir jų modelius lyginamoji analizė bei sukurtas laisvojo aerostato pilotų licencijuotų pilotų kompetencijų teorinis modelis. Jame yra keturios sudėtinės dalys: greta... [toliau žr. visą tekstą] / The problem is that there are no training methodology of an unrestricted aerostat pilots, which would meet the requirements of the Federation Aeronautique Internationale (FAI) and European Union standarts and directives. Investigations of Lithuanian air balloons sporting organizations have shown the need for improved air pilot training model that meets the requirements of the Federation Aeronautique Internationale (FAI) and European Union standarts and directives and the need to improve pilots (starting with students and ending with elderly people) training system and increase Lithuania ballooning Society by enlarging it‘s geography. The aim – to create the model of an unrestricted aerostat pilots training in Lithuania. The object - model of licensed unrestricted aerostat pilots training in Lithuania The goals: 1) Review the professional competence of specialists and licensed unrestricted aerostat pilot in theoretical aspects. 2) Create theoretical model of unrestrictedaerostat pilot‘s competencies. 3) To prepare research methodology for empirical investigation and create questionnairy for Lithuanian hor air balloon sport organizations. 4) Substantiate the training model of licensed unrestricted aerostat pilots. Research methods: scientific literature analysis, questionnaire survey and statistical data analysis. The work consists of three parts. First is comparative analysis of theoretical aspects about the competencies and their models published in the literature... [to full text]

L'étude réalisée au cours de cette thèse s'intéresse au fluage secondaire de gainages de Zircaloy-4 détendu dans des conditions représentatives d'un Accident de Perte de Réfrigérant Primaire (APRP) dans le circuit primaire d'un réacteur à eau pressurisée. Elle s'intègre dans le cadre du projet ANR PERFROI. Ce travail s'articule autour de trois axes que sont la conception d'essais de fluage à haute température et en pression interne sur des gaines, leur réalisation et exploitation, la modélisation de ces essais et la caractérisation du comportement au fluage secondaire de cet alliage, et l'étude du fluage secondaire d'éprouvettes de Zr-4 pré-oxydées. Le banc d'essai est conçu pour induire un chargement thermique hétérogène le long des éprouvettes tubulaires testées en utilisant un chauffage par induction. Le fluage à haute température des métaux est très dépendant de la température. Ce gradient thermique couplé à une pression interne mène alors à une déformation hétérogène de l'éprouvette dans l'axe du tube. En réalisant plusieurs chargements en pression interne, plusieurs conditions thermo-mécaniques sont appliquées en un seul essai. Les essais sont instrumentés de manière à mesurer les distributions cinématique et thermique dans une région de 20 mm située entre les spires de l'inducteur. Deux méthodes d'analyse d'images numériques sont adaptées dans ce but et ont été validées par des essais dédiés. Les essais sont modélisés sous le logiciel commercial ABAQUS6.11-2. Un recalage d'une loi de fluage secondaire est réalisé, par des calculs éléments finis intégrés dans un solveur de Gauss-Newton. Cette démarche est validée avec un essai virtuel puis appliquée à 9 essais réalisés sur des échantillons de Zr-4 vierge. Les résultats permettent de déterminer à la fois l'influence de la température et du chargement mécanique de manière fine pour la gamme de température et pression souhaitée. Ils mettent en évidence un changement brutal de comportement à une température de 810 °C, correspondant au début de la transition de la phase alpha vers un matériau biphasé. De plus, les exposants de Norton identifiés dans le domaine alpha pour des contraintes inférieures à 25 MPa sont de l'ordre de l'unité, et entre 4 et 5 pour les contraintes supérieures. Ces ordres de grandeurs sont respectivement associés dans la littérature à des mécanismes de fluage par diffusion et dislocation. Au-dessus de 810 °C, les caractéristiques associées dans la littérature à la superplasticité sont mis en évidence : l'exposant de Norton est compris entre 2,5 et 3,5 et l'énergie d'activation est supérieure à 300 kJ/mol. Des essais sont enfin menés sur des éprouvettes seulement pré-hydrurées, puis pré-oxydées et pré-hydrurées. Les mesures réalisées pendant ces essais sont associées à des métallographies pour mettre en évidence l'effet des couches de zircone et de phase alpha enrichie en oxygène sur la déformation de la gaine à 800 °C. / The present work investigates the steady-state creep behavior of Stress Relieved Annealed Zircaloy-4 claddings under thermo-mechanical conditions simulating a Loss-Of-Coolant Accident (LOCA) in a primary loop of Pressurized Water Reactors. It is part of the PERFROI project focusing on the flow blockage within fuel rods bundle and its potential impact on the cool ability of a nuclear core reactor. The present work includes three main elements that are (a) the design, the performance and the processing of an innovative experiment, (b) the modeling of the tests and the determination of steady-state creep constitutive laws at temperatures ranging from 750 to 850 °C and (c) the preliminary study of the corrosion effect on the Zr-4 claddings creep behavior. An experiment addressing to heterogeneous thermal conditions was designed using an induction heating device. The creep behavior of metals at high temperatures is known to be very sensitive to the temperature. Under an internal pressurization of the cladding this thermal gradient induces its heterogeneous deformation. Using this configuration and three successive internal pressure loadings with a single experiment a lot of thermal mechanical conditions are available. Both thermal and kinematics full field measurements are performed into a 20 mm gauge length located between the induction coils using respectively near infra-red thermography and two dimensional digital image correlation. These two key digital image methods are assessed using dedicated experiments. The tests are modeled using the ABAQUS commercial software. The expected creep behavior law is updated using finite element model calculations included into a Gauss-Newton solver. The method was validated using virtual experiments and then applied to the actual tests. A high consistency between the experiments is obtained and is in agreement with available literature data. Norton exponent and activation energy maps are plotted into the thermal mechanical condition range of interest. These parameters highlight changes of dominant deformation mechanisms in the alpha-phase domain at a 26 MPa von Mises stress and of micro-structure at an 810 °C temperature (at which phase transformation is expected). In the mixed phase domain, the material parameters are similar to those associated in the literature data with super plasticity deformation mechanism. Finally, experiments are performed on pre-oxidized samples at 800 °C. The rupture of the outer zirconia and oxygen enriched alpha layers is observed during the test at a 1.1\% hoop strain.

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Next-generation and present fusion devices such as the Joint European Torus (JET) aim for plasma operations in H-mode, a plasma regime with high confinement and low loss of energy and fuel that results from a barrier for heat and particle transport at the plasma edge, the pedestal. Due to steep gradients of the density, temperature and pressure profiles, the pedestal experiences instabilities called Edge-localized-modes (ELMs) which lead to large fluxes of heat and particles that might damage machine components. A theoretical value for the critical threshold for the pressure gradient is determined by the Peeling-Ballooning (PB) model. Although this model has been rather reliable, experiments have shown a discrepancy between the experimental pedestal pressure gradient and the critical pressure gradient determined by the model. A number of experimental gradients were significantly lower than the predicted gradients. The mechanisms responsible for this discrepancy are not fully understood yet. The present hypothesis identifies the relative shift between the positions of the temperature and density pedestals and neutral pressure as key parameters, related to input power and gas dosing among other engineering parameters. Further impact could arise from the assumption of equal ion and electron temperature and the neglecting of the plasma rotation (velocity). In order to investigate this issue more thoroughly, JET established a comprehensive database containing pedestal characteristics. As a part of this work, a software has been implemented to visualize the data since such a tool did not exist yet. The tool enables the plotting of pedestal related parameters while specific data subsets can be selected or neglected. The tool has been used to investigate the impact of ion temperature and plasma rotation on the discrepancy between the theoretical and experimental critical gradients. Hereby, many relevant parameters needed to be constrained to observe an isolated impact of ion temperature and plasma rotation. The results of this investigation support the hypothesis that mainly the relative shift affects the discrepancy between experimental and predicted pressure gradient, but that also the use of experimental ion temperature can contribute to reduce the discrepancy. / Nästa generations och nuvarande fusionsanordningar, såsom Joint European Torus (JET), syftar till plasmaoperationer i H-läge, en plasmaregim med hög inneslutning och låg förlust av energi och bränsle som är ett resultat av en barriär för värme­ och partikeltransport vid plasmakanten, piedestalen. På grund av branta gradienter i densitets-, temperatur- och tryckprofilerna, är piedestalen instabil. Instabiliteten kallas Edge-Localised-Mode (ELM) och leder till stora flöden av värme och partiklar som kan skada maskinkomponenter. En kritisk tröskel för tryckgradienten bestäms av modellen Peeling-Ballooning (PB). Även om denna modell har varit ganska tillförlitlig, har experiment visat en diskrepans mellan den experimentella piedestaltryckgradienten och den kritiska tryckgradienten som bestäms av modellen. Ett antal experimentellt uppmätta kritiska gradienter är signifikant lägre än de förväntade enligt modellen. De mekanismer som ligger bakom denna diskrepans är ännu inte helt klarlagda. Den nuvarande hypotesen identifierar skillander i pos positionen av temperature- och täthetspiedestalen, samt trycket från neutraler som nyckelparametrar, relaterade till inmatad effekt och gasdosering bland andra ingenjörparametrar. Ytterligare påverkan kan uppstå genom antagandet att joner och elektroner har samma temperatur och försummandet av plasmarotationen. För att undersöka denna fråga mer ingående upprättade JET en omfattande databas med piedestalegenskaper. Som en del av detta arbete har en programvara implementerats för att visualisera data eftersom ett sådant verktyg inte funnits tidigare. Verktyget möjliggör plottning av piedestalrelaterade parametrar medan specifika data delmängder kan väljas eller väljas bort. Verktyget har använts för att undersöka inverkan av jontemperatur och plasmarotation på diskrepansen mellan teoretiska och experimentell kritiska tryckgradienten. För denna analys behövde många relevanta parametrar begränsas för att observera en isolerad påverkan av jontemperatur och plasmarotationen. Resultaten av denna undersökning stödjer hypotesen att det relativa skiftet främst påverkar diskrepansen mellan experimentell och förutsedd tryckgradient men att även användning av experimentell jontemperatur kan bidra till att minska diskrepansen.

This research deals with impacts of pesticide substances on spider populations. In this case pesticides of the neonicotinoids classes were tested. Specific neonicotinoids were applied to different of spiders which were collected in various localities and at some stage of development - nymph, adult or subadult individuals. The diploma thesis analyzes and the documents the effects of neonicotinoids to spiders. The results show that some pesticides can have a significant negative effect to locomotion, predation, ballooning, drop or to spiders mortality. Keywords: spider, arthropod, pesticides, insecticides, neonicotinoids, sublethal effects, mortality, EthoVision XT, locomotion, drop, ballooning, predation, Philodromus, Oedothorax, Pardosa, Xerolycosa, Phylloneta