Experimental Investigation of Accelerator Driven Nuclear Reactors for Thorium Based Nuclear Power

Tato diplomová práce se zabývá problematikou spojenou využitím thoria jako jaderného paliva v urychlovačem řízených systémech. V této práci je popsán princip ADS, jejich současná situace a možnosti využití do budoucna. Tato práce je blíže zaměřená na určení neutronového toku ve spalačním terči QUINTA. V prosinci 2013 byl proveden experiment, ve kterém byla uskutečněna tři ozařování kobaltových vzorků v různých pozicích spalačního terče QUINTA, který se nachází ve Spojeném ústavu jaderných výzkumů, Dubna. Vzorky Co-59 byly ozařovány v poli neutronů generovaných deuterony o energii 2 AGeV a 4 AGeV a částicemi C-12 o energii 2 AGeV při spalační reakci. Tyto vzorky byly měřeny pomocí polovodičových detektorů ze superčistého germania a analyzovány použitím jaderné gama spektrometrie. Byly určeny reakční rychlosti produktů reakcí v Co-59, ze kterých byl určen tok neutronů v sestavě QUINTA. Experimentální reakční rychlosti byly porovnány s výpočtem s pomocí MCNPX kódu.The Master Thesis deals with the use of thorium nuclear fuel in accelerator driven systems. Basic principle of ADS, present situation and future possibilities are described in this work. The main goal of the work is determination of neutron flux in spallation target QUINTA. In December 2013, an experiment was performed at Joint Institute for Nuclear Research, Dubna. Samples of cobalt, situated at different positions in QUINTA target, were irradiated in secondary neutron field generated by deuteron beam of energies 2 AGeV and 4 AGeV and beam of C-12 with energy 2 AGeV. The samples were measured with the use of germanium semiconductor detectors and analysed using gamma-ray spectrometry. Reaction rates of Co-59 products were determined. Neutron flux was determined in setup QUINTA on the base of experimental reaction rates. Experimental reaction rates were compared with calcula1tion of MCNPX code.

End Stop Unit of Hydraulic Jack

Import 29/09/2010Cílem práce je za pomoci laserové závory zabránit zničení majetku při manipulaci s hydraulickým zvedacím zařízením. Ve stručnosti je uvedena historie a princip laseru a také popis použitého hydraulického zvedacího zařízení. Práce popisuje zapojení jednotky do ovládací struktury a její vyladění pro bezproblémovou obsluhu a fungování. Je popsána praktická realizace zapojení laserové závory a její odzkoušení před samotným spuštěním. V závěru jsem zhodnotil celý postup a výhody laserové závory při řešení této realizace. Rovněž jsem vypracoval uživatelskou příručku pro obsluhu hydraulického zvedacího zařízení s připojenou jednotkou koncového dojezdu.The target of this work is to help the laser gate increase safety of persons and above all property in the handling of a hydraulic jack device. In brief is introduced the history and principles of lasers and laser gate and a simplified description of the hydraulic jack. This work describes the involvement of the control structure and its tuning for smooth operation and functioning. It describes the practical realization of the integration of laser gate and its testing before the launch. In conclusion, I reviewed the whole process and benefits of laser sensors in the solution of this realization. I made a user manual.Prezenční448 - Katedra elektronikyvelmi dobř

Environmental Effects among Differently Located and Fertile Sites on Forest Basal-Area Increment in Temperate Zone

Environmental properties differently influence the growth of forest tree species. The antagonistic effects of variable environmental properties classify the forest response according to various tree compositions among different sites. The division of the forest response was assessed in 52 stands arranged into 26 types of 13 site management populations (MPs) in 5 areas in the Czech Republic territory. The assessment was performed using time-series multiple regressions of basal-area increment from pure immature stands of Norway spruce (Picea abies), Scots pine (Pinus sylvestris), oaks (Quercus sp.), ash (Fraxinus excelsior) and willows (Salix sp.) dependent on the interpolated average temperatures, annual precipitation, atmospheric concentrations of SO2, NOx and O3 and soil properties over the period 1971-2008 at p < 0.05. Site MPs differentiated the forest response to a greater extent than tree species. The response of the forests was significantly distributed by means of the montane, upland and waterlogged sites. The multiple determination index (r2) GREATER-THAN OR EQUAL TO 0.6 indicated an adaptable tree increment but an interval of r2 between 0.80-0.92 implied forest sensitivity to variability in environmental properties on non-waterlogged sites. The index r2 < 0.6 suggested a fluctuating forest increment that reflects environmental variability inconsistently. The fluctuating increment most affected the spruce and pine stands grown from upland to submontane locations. Montane spruce stands, as well as rock pines, appeared to be one of the most sensitive ones to environmental change. Floodplain forests seemed as adaptable to variable environmental properties.O

A Historical Review of Principles Guiding the Formulation of Methods for Stature Estimation Based on the Human Skeleton

Z historického přehledu principů tvorby metod pro odhad výšky postavy člověka na základě skeletu vyplývá, že lze vymezit čtyři základní skupiny metod: metody podílové, regresní, anatomické a metody organické korelace. Každá má svá specifika a úskalí, která bezprostředně vyplývají z jejich matematické konstrukce. Nejčastěji se k odhadu výšky postavy používají některé rozměry dlouhých kostí končetin. Bylo teoreticky prokázáno, že nejpřesnější možné odhady poskytují metody regresní, zejména když k odhadu využijeme kombinaci rozměrů z více kostí. Nutným předpokladem použití lineární regrese je však užití pouze těch rovnic, které byly vytvořeny na základě výběru z populace, z níž pochází i odhadovaný jedinec. V opačném případě, tj. pokud je lineární regrese použita pro odhad jedinců z populace jiné, může dojít k menšímu či většímu vychýlení odhadu. Tato skutečnost byla již mnohokrát empiricky ověřena. Teoretický rozbor lineární regrese ukázal, že jde o důsledek jevu označovaného jako „regrese k průměru“. Metody organické korelace (založené na minimalizaci součtu plochy reziduálních trojúhelníků) jsou méně náchylné k systematické chybě, jsou však také méně přesné. Lze je ale aplikovat na libovolnou populaci a pro jednotlivé případy z neznámé populace jsou nejpřesnější. Anatomické metody jsou aplikovatelné jen v případě dostatečně zachovaného skeletu. Jsou založeny na součtu výšek všech (nebo téměř všech) kostí skeletu, které se na výšce postavy přímo podílejí. Rozdíl mezi výškou postavy za života a součtem délek kostí skeletu od lebky po patní kost se pohybuje v řádu centimetrů a prostor pro chybu odhadu je tak malý. Ať už pak k odhadu výšky ze skeletu v rámci anatomické metody použijeme kterýkoliv ze tří výše uvedených matematických postupů (podílová metoda, lineární regrese, organická korelace), rozdíly mezi jimi pořízenými odhady jsou zanedbatelné a jejich rozlišování pozbývá smyslu. Celkově jsou tedy anatomické metody nejpřesnější a je třeba je doporučit, kdykoliv to stav zachování skeletu dovolí.A historical review of principles guiding the formulation of methods for stature estimation based on measurements of the human skeleton reveals that it is possible to delimit four basic groups of methods: anatomical, constant ratio, linear regression, and organic correlation methods. Each has its own specific features and limits, which are a result of their mathematical constructions. Long bones of limbs are most often used for estimates of stature. It was demonstrated theoretically that linear regression models provide the most precise and accurate estimates of stature from particular skeletal elements, especially when several suitable bones are used in combination. A necessary condition for using the linear regression equations is, however, that we use equations based on the population from which the estimated individual originated. In contrast, when a regression equation is applied to an individual originating from a different population smaller or larger systematic error of the estimate may result. This fact was assessed empirically on numerous occasions and it was demonstrated on the basis of linear regression theory that a phenomenon known as “regression to the mean” can be considered as the cause. Organic correlations (built on the least-triangle area criterion) are less prone to systematic errors, but they are also less precise. They can be applied to any population and are best suited for cases where the population of origin is unknown. Anatomical methods are best applied when the skeleton is adequately preserved as this method requires bone lengths of all (or almost all) bones contributing to body height. The difference between height of the living body and the sum of lengths of relevant bones from head to heel is in the order of centimeters so the estimate error margin is small. Consequently, the differences between estimates obtained from using the different mathematical approaches (constant ratio, linear regression or organic correlation) are insignificant, so there is little benefit in preferring any particular one. Overall, anatomical methods provide the most accurate and precise results for height estimation and should be recommended wherever allowed by the state of preservation of the skeleton

ANALYSIS OF NEUTRON FIELDS GENERATED IN SPALLATION TARGETS OF B-URAN EXPERIMENTAL ASSEMBLY USING MONTE CARLO METHOD

The aim of this paper is to introduce experimental assembly B-URAN and the results of Monte Carlo simulations of neutron fields, which will be generated by using various spallation targets. This experimental assembly was constructed in Joint Institute of Nuclear Research in Dubna, Russian Federation, in order to study accelerator driven systems fundamental characteristics. Beam of 660 MeV protons should be used for that purpose. The MCNP model of such set-up has been developed at Brno University of Technology, Czech Republic. The goal is to get data needed for prediction of reaction rates in detectors placed in B-URAN experimental channels. Such data will be experimentally validated later. Furthermore, simulations of radiation exposure around this xperimental assembly were performed

Pleiotropic effects of niacin: Current possibilities for its clinical use

Niacin was the first hypolipidemic drug to significantly reduce both major cardiovascular events and mortality in patients with cardiovascular disease. Niacin favorably influences all lipoprotein classes, including lipoproteina,and belongs to the most potent hypolipidemic drugs for increasing HDL-C. Moreover, niacin causes favorable changes to the qualitative composition of lipoprotein HDL. In addition to its pronounced hypolipidemic action, niacin exerts many other, non-hypolipidemic effects (e.g., antioxidative, anti-inflammatory, antithrombotic), which favorably influence the development and progression of atherosclerosis. These effects are dependent on activation of the specific receptor HCA2. Recent results published by the two large clinical studies, AIM-HIGH and HPS2-THRIVE, have led to the impugnation of niacin’s role in future clinical practice. However, due to several methodological flaws in the AIM-HIGH and HPS2-THRIVE studies, the pleiotropic effects of niacin now deserve thorough evaluation. This review summarizes the present and possible future use of niacin in clinical practice in light of its newly recognized pleiotropic effects

New experimental research stand SVICKA neutron field analysis using neutron activation detector technique

Knowledge of neutron energy spectra is very important because neutrons with various energies have a different material impact or a biological tissue impact. This paper presents basic results of the neutron flux distribution inside the new experimental research stand SVICKA which is located at Brno University of Technology in Brno, Czech Republic. The experiment also focused on the investigation of the sandwich biological shielding quality that protects staff against radiation effects. The set of indium activation detectors was used to the investigation of neutron flux distribution. The results of the measurement provide basic information about the neutron flux distribution inside all irradiation channels and no damage or cracks are present in the experimental research stand biological shielding

Generated heat by different targets irradiated by 660 MeV protons

Calorimetric experiments have been performed to analyze different thick targets of natU, C, Pb material, irradiated by 660 MeV protons at the Phasotron accelerator facility, Joint Institute for Nuclear Research (JINR) in Dubna, Russia. The method of online temperature measurement has been compared with MCNPX 2.7.0 simulation and selected with Ansys Transient Thermal Simulation to compare measured temperature with the simulated one. Thermocouples type T and E have been used as a temperature probe. Many different positions have been measured for each target. Temperature results are following very well the processes inside of the cylinders. Changes of heat deposition caused by drops of the proton beam intensity are displayed very well as a jagged line shown in almost every chart. Accurate temperature changing measurement is a very modest variation of how to observe inner macroscopic behavior online

Experimental investigation and Monte Carlo simulations of radionuclide production inside the Uranium spallation target QUINTA irradiated with a 660-MeV proton beam

The accelerator-Driven-System (ADS) is very important to study the neutron field and radionuclide production inside simple-geometry uranium subcritical setups irradiated with high energy particle beams. A subcritical setup QUINTA was irradiated with the 660-MeV proton beam from Phasotron accelerator at the Joint Institute for Nuclear Research (JINR). The radionuclide production in the region along the beam axis was investigated by the activation technique. The aim was to compare (n,x) with (p,x) reactions using activation detectors of 59Co and natPb, and compare experimental results with the calculated results using Monte Carlo simulation code MCNPX 2.7