|
HYDROGEN ABSORPTION IN A-Co30Fe55B15
Čermák, Jiří ; Král, Lubomír ; Roupcová, Pavla
Hydrogen solved in amorphous alloys (AAs) influences their magnetic characteristics. AAs are also perspective\nas additives that can improve hydrogen storage kinetic in certain types of ball-milled hydrogen storage\nmaterials (HSMs). Therefore, knowledge of hydrogen solubility and hydrogen sorption kinetics in AAs are of a\ngreat importance for aimed design both AAs with optimal magnetic parameters and HSMs with desired sorption\ncharacteristics. In the present paper, amorphous alloy Co30Fe55B15 (an example of the type a-TM1xTM2y Bz ;\nTM - transition metal) was investigated. Hydrogen concentration c H was measured by Sieverts method in\ntemperature interval from T = 150 °C to T = 350 °C under hydrogen pressure p up to 6 MPa. It was found that\nc H was an increasing function of p and its maximum value was typically 0.5 wt.% H2 at 350 °C and 6 MPa.\nHowever, when the alloy was preliminary hydrogen charged (PHC), the pressure dependence of total c Htot in\nthe first absorption cycle(s) is non-monotonous in dependence on PHC conditions. For the sake of comparison,\nthe same absorption characteristics were measured also in Mg2Ni intermetallic that is a common constituent\nin Mg-based HSMs. Comparing Co30Fe55B15 and Mg2Ni, it was concluded that Co30Fe55B15 shows lower\nhydrogen solubility, but much better absorption kinetics.
|
|
ELECTRON BEAM REMELTING OF PLASMA SPRAYED ALUMINA COATINGS
Matějíček, Jiří ; Veverka, J. ; Čížek, J. ; Kouřil, J.
Plasma sprayed alumina coatings find numerous applications in various fields, where they enhance the properties of the base material. Examples include thermal barriers, wear resistance, electrical insulation, and diffusion and corrosion barriers. A typical structure of plasma sprayed coatings, containing a multitude of voids and imperfectly bonded interfaces, gives them unique properties - particularly low thermal conductivity, high strain tolerance, etc. However, for certain applications such as permeation barriers or wear resistance, these voids may be detrimental.\nThis paper reports on the first experiments with remelting of plasma sprayed alumina coatings by electron beam technology, with the purpose of densifying the coatings and thereby eliminating the voids. Throughout the study, several parameters of the e-beam device were varied - beam current, traverse velocity and number of passes. The treated coatings were observed by light and electron microscopy and the thickness, structure and surface morphology of the remelted layer were determined and correlated with the process parameters. Based on the first series of experiments, the e-beam settings leading to dense and smooth remelted layer of sufficient thickness were obtained. In this layer, a change of phase composition and a marked increase in hardness were observed.\n
|
|
The GIS support to measures on the ground in case of leakage of liquid pollutant on the road
Kolejka, Jaromír ; Rapant, P. ; Zapletalová, Jana
Accidents on roads associated with the leakage of hazardous substances are one of the major challenges encountered by disaster management. Because of the impossibility of predicting the place and time of the event, then it is necessary in the event of such an accident to proceed in quick succession of steps. They are designed primarily to protect human life and health, and then to minimize to property and environment damage. The paper describes the response to this event using GIS tools and generally available geodata. The simulated accident on the D1 highway near Ostrava is applied as a demonstration example.
|
|
Key sequence in the films of directors who work with long sequence shots and with stylization
Ruzyak, Pavel ; BERNARD, Jan (advisor) ; KLEPIKOV, Milan (referee)
This thesis wants to explore long shots alongside with stylization in cinema.
Through three directors are explored possibility and problematic of cinematographic expression through long shots and stylization. Stylisation is connected mainly with mis-en-scène and particular aspects of it – acting, film decoration/props, film space, film sound,...
The terms stylisation and long shot (plan-séquence) are analysed and explored on its own and in the films of the chosen directors.
The main analysed directors are Andrei Tarkovsky, Carl Th. Dreyer and Béla Tarr and their three films (in the same order) - Sacrifice, Gertrud and Satantango.
The chosen directors are from my point of view the best example of the use of stylisation and long shots due to their artistic clarity and coherence.
I try to base this work mostly on my own analysis and thoughts about long shots and stylisation based on the literature, films and my own film works, although I also use quotations from directors/authors and quotations from theoretical works.
The thesis in its form is closest to the analytic and essay study.
|
| |
|
Animal from the Garry Winogrand´s point of view
Tvarůžka, Václav ; DVOŘÁK, Tomáš (advisor) ; Ledvina, Josef (referee)
Work is an introduction to the work of Gary Winogrand and also analysis of the issue of limited possibility of looking which manifests in the particular problem, of impossibility of looking at animal. Work is based on essay from John Berger who concludes this communication problem trough the rise of capitalism and lost connection between human and animal creature. This thing is also connected to the phenomenon of zoological garden. Work is set in this certain context and further it is analyzing the photographs from Winogrand himself and also other authors, which are dealing with affinity problems like for example problem of authenticity (in the photography with the motive of animal), which is represented by Joan Fontcuberta. Or the problem of anthropomorphization (Walt Disney).
|
| |
|
Neural Networks Between Integer and Rational Weights
Šíma, Jiří
The analysis of the computational power of neural networks with the weight parameters between integer and rational numbers is refined. We study an intermediate model of binary-state neural networks with integer weights, corresponding to finite automata, which is extended with an extra analog unit with rational weights, as already two additional analog units allow for Turing universality. We characterize the languages that are accepted by this model in terms of so-called cut languages which are combined in a certain way by usual string operations. We employ this characterization for proving that the languages accepted by neural networks with an analog unit are context-sensitive and we present an explicit example of such non-context-free languages. In addition, we formulate a sufficient condition when these networks accept only regular languages in terms of quasi-periodicity of parameters derived from their weights.
Fulltext: content.csg -  PDF
Plný tet: v1237-16 - PDF
|
|
Fish passes and their role in landscape and ecosystem management
Míka, Martin ; Horký, Pavel (advisor) ; Kuříková, Pavlína (referee)
Fishways are devices intended to restore fish migration through the transverse obstacles in fragmented flows. Basic types of fish passages can be divided into technical and close to nature. Technical as cellular or crevice between the close to nature can include, for example, a bypass channel or boulder ramps. Close to nature fishways are suitable not only for Migration wider range of species and the size of fish, but they are preferable as landscape elements in urban landscapes. Can be recommended to be close to nature when crossing streams fragmented preferred, although not necessarily their use, for example, due to space constraints at a particular location possible.
|
|
DCTOOL-A3
Bakule, Lubomír ; Papík, Martin ; Rehák, Branislav
DCTOOL-A3 is a documentation of Matlab routines developed for the design of decentralized control of large scale complex systems. The current beta version covers three areas as follows:\nReport 4.1 deals with the event-triggered control design for unstructured uncertain systems. Both non-quantized and quantized feedback is analyzed. The results are given in terms of linear matrix inequalities (LMIs). Logarithmic quantizer is used. Numerical example illustrates the effectiveness of the presented results.\nReport 4.2 presents a new decentralized overlapping wireless control design with a switched communication protocol. The method is applied by simulations on the 20-story building structure including the test of robustness of the methods against sensor failures and network node dropouts of a digital network.\nReport 4.3 presents the construction of a new decentralized wireless controller and a set of heuristic algorithms for evaluation of packet dropouts, sensor faults and actuator faults. The digital network operates at the standard frequency used in well-known widely-used industrial protocols. The results are tested at the Benchmark model decomposed into two disjoint substructures. The results are published. Thus, the details are omitted here.
|
guest ::
