Process Rationalization of Reishauer Rolling Gear Grinding

Import 02/11/2016Bakalářská práce se zabývá problematikou procesu odvalovacího broušení ozubení Reishauer a možností zvýšení efektivity stávajícího výrobního zařízení. V úvodu je popsána teorie odvalovacího broušení, nástroje pro broušení ozubení a strojní vybavení. Poté následuje popis stávající technologie a problematiky na výrobní lince. Hlavní část práce se zabývá praktickou zkouškou nového progresivního brousícího nástroje, zvoleného pro racionalizaci procesu broušení ozubení. Závěrem je technicko-ekonomické zhodnocení výrobního procesu po zavedení nového nástroje do výroby.Bachelor thesis deals with questions of generating gear grinding process Reishauer and possibilities of increasing efficiency of current manufacturing equipment. The introduction describes theory of generating gear grinding process, grinding tools and machines. The following part describes current technology and problematics of gear production line. Main part of thesis deals with practical try-out of new progressive grinding tool, which was selected to improve gear grinding process. Finally thesis describes evaluation of manufacturing process improvement by economical and performance point of view.346 - Katedra obrábění, montáže a strojírenské metrologievýborn

The magnetic reversal in dot arrays recognized by the self-organized adaptive neural network

The remagnetization dynamics of monolayer dot array superlattice XY 2-D spin model with dipole-dipole interactions is simulated. Within the proposed model of array, the square dots are described by the spatially modulated exchange-couplings. The dipole-dipole interactions are approximated by the hierarchical sums and spin dynamics is considered in regime of the Landau-Lifshitz equation. The simulation of reversal for $40 000$ spins exhibits formation of nonuniform intra-dot configurations with nonlinear wave/anti-wave pairs developed at intra-dot and inter-dot scales. Several geometric and parametric dependences are calculated and compared with oversimplified four-spin model of reversal. The role of initial conditions and the occurrence of coherent rotation mode is also investigated. The emphasis is on the classification of intra-dot or inter-dot (interfacial) magnetic configurations done by adaptive neural network with varying number of neurons.Comment: 16 figure

Properties of iterative Monte Carlo single histogram reweighting

We present iterative Monte Carlo algorithm for which the temperature variable is attracted by a critical point. The algorithm combines techniques of single histogram reweighting and linear filtering. The 2d Ising model of ferromagnet is studied numerically as an illustration. In that case, the iterations uncovered stationary regime with invariant probability distribution function of temperature which is peaked nearly the pseudocritical temperature of specific heat. The sequence of generated temperatures is analyzed in terms of stochastic autoregressive model. The error of histogram reweighting can be better understood within the suggested model. The presented model yields a simple relation, connecting variance of pseudocritical temperature and parameter of linear filtering.Comment: 3 figure

Give me liberty or give me money: the fiscal decentralization and autonomy of regional governance in Slovakia

[Abstract] The aim of this study is to focus on fiscal decentralization and regional financial autonomy in Slovakia. The public administration reform and fiscal decentralization process in Slovakia ought to increase the autonomy of the multi-level governance and to decrease its dependency on state budgeting and other transfers. We argue that regional territorial governance is greatly dependent on financial incentives from central state financing, which limits the expected effect of decentralization and regional fiscal autonomy. By collecting quantitative data on state transfers and revenues to regional governments we demonstrate the limits of spatial, financial and decision-making autonomy within particular regions. The selected time frame 2005-2016 reflects all stages, reforms and changes in the fiscal decentralization of the second level governance in Slovakia

Utilization of biomass energy

Obnovitelné zdroje energie a jejich rozvoj přináší otázky jak tyto zdroje co nejlépe využít. Hlavním cílem mé bakalářské práce je seznámení se způsoby přeměny biomasy na energetický potenciál a jeho využití. Poté je uveden vlastní návrh bioplynové stanice a výpočet množství vyprodukované elektrické energie ve zvolené kogenerační jednotce na základě údajů o měrné produkci exkrementů chovaných prasat a produkci bioplynu z kejdy. Výsledkem je zhodnocení ekonomiky provozu bioplynové stanice pro zemědělský podnik podle počtu chovaných prasat a možnosti využití elektrické energie.Restoring sources of a energy and their development brings questions how these can be these sources the best utilized. The main aim of my bachelor`s thesis is an acquainted with methods of biomass conversion to energetic potential and his advantage. Than is mentioned proper project of the biogas plant and calculation of produced electric energy quantity in select cogeneration unit base on data on specific excrements production bred pigs and biogas production from slurry. The result is a variant evaluation of economy of the biogas plant operation for agricultural enterprise according to number of bred pigs and possibility of electric energy utilization.

The biological significance of changes in the vascular wall and atherosclerotic plaque for the development of atherosclerotic disease of the coronary arteries

Akutní komplikace aterosklerózy jsou typicky způsobené tepenným uzávěrem na podkladě akutní trombózy formující se v místě ruptury tzv. vulnerabilního aterosklerotického plátu (VP). Včasná identifikace VP by mohla napomoci těmto příhodám předcházet. Současné metody pro zhodnocení kardiovaskulárního rizika jsou zaměřeny na opatření na populační úrovni a pro zhodnocení rizika individuálního jedince nejsou dostatečně citlivé a specifické. Disertační práce se proto zabývala možnostmi in vivo detekce VP pomocí biomarkerů a zobrazovacích metod. V první části práce jsme se soustředili na detekci mikroRNA (miR), které jsou v posledních letech zkoumány jako slibné biomarkery celé řady onemocnění včetně aterosklerózy. Hladiny miR jsme určovali pomocí kvantitativní polymerázové řetězové reakce ve vzorcích periferní žilní krve pacientů ve velmi časné fázi infarktu myokardu s elevací ST segmentů (STEMI), kteří sloužili jako nejbližší klinický model akutní ruptury VP. Výsledky vedly k identifikaci dvou miR (miR-331 a miR-151-3p), které byly deregulovány u STEMI a mohly by být biomarkery VP. V další části výzkumu jsme se zabývali možnostmi invazivního zobrazení VP pomocí intravaskulárního ultrazvuku a blízké infračervené spektroskopie (IVUS a NIRS). Potvrdili jsme možnost bezpečné detekce NIRS dat v karotických...Acute complications of atherosclerosis are typically caused by arterial occlusion due to acute thrombosis forming over a ruptured vulnerable atherosclerotic plaque (VP). Early identification of such VP prior to their rupture could help prevent these events. At the same time, methods for assessing cardiovascular risk are focused on measures at the population level and are not sensitive and specific enough to assess the risk of individual patients. We therefore focused on the possibilities of in vivo detection of VP using biomarkers and invasive imaging methods. First, we focused on the detection of microRNAs (miRs), which have been investigated in recent years as promising biomarkers for a number of diseases, including atherosclerosis. We determined miR levels using quantitative polymerase chain reaction in peripheral venous blood samples from patients in very early phase of ST-elevation myocardial infarction (STEMI), which served as the closest clinical model of acute VP rupture. The results led to the identification of two miRs (miR-331 and miR-151-3p) that were deregulated in STEMI and could be biomarkers of VP. In the next part of the research, we dealt with the possibilities of invasive imaging of VP using intravascular ultrasound and near- infrared spectroscopy (IVUS and NIRS). We confirmed...Kardiologická klinikaDepartment of Cardiology2. lékařská fakultaSecond Faculty of Medicin

A self-adjusted Monte Carlo simulation as model of financial markets with central regulation

Properties of the self-adjusted Monte Carlo algorithm applied to 2d Ising ferromagnet are studied numerically. The endogenous feedback form expressed in terms of the instant running averages is suggested in order to generate a biased random walk of the temperature that converges to criticality without an external tuning. The robustness of a stationary regime with respect to partial accessibility of the information is demonstrated. Several statistical and scaling aspects have been identified which allow to establish an alternative spin lattice model of the financial market. It turns out that our model alike model suggested by S. Bornholdt, Int. J. Mod. Phys. C {\bf 12} (2001) 667, may be described by L\'evy-type stationary distribution of feedback variations with unique exponent $\alpha_1 \sim 3.3$. However, the differences reflected by Hurst exponents suggest that resemblances between the studied models seem to be nontrivial.Comment: 19 pages, 9 figures, 30 reference

Example of low information capability of projected parameters for lifetime extension of high pressure vessels

Zobecnění informací, získaných na jednom kotli pro kotle dalších bloků elektráren, postavených ve stejné době a zhruba i stejně provozovaných je obecně používaný postup. Uvedený příspěvek ukazuje, že ne vždy je možné tento postup použít.Generalized procedure for boilers and high pressure vessel lifetime assessment is usage of creep data and roughly the same operation time between boilers. This paper present results that this procedure is not always possible to use