National Repository of Grey Literature 154 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Influence of nanoparticles and polymers on the amyloid fibril formation
Holubová, Monika ; Štěpánek, Petr (advisor) ; Štěpánek, Miroslav (referee) ; Nardin, Corrine (referee)
The thesis deals with the testing of amyloidogenicity of various carbon nanoparticles and polymers. The first part of the thesis provides the theoretical background of amyloidoses, a group of diseases in which proteins are stored in the insoluble form of amyloid. In addition, the theoretical part also deals with a general overview of nanomaterials and the most important methods. Several types of nanomaterials were tested within the thesis, so the part Results and Discussion was divided into two subchapters: 1) Carbon nanospecies and amyloid fibril formation, and 2) Polysaccharides, glycogen modifications and amyloid fibril formation. The first subchapter concerns the testing of four types of carbon nanoparticles (single-walled carbon nanotubes (SWNT), fullerenes (C60), carbon quantum dots (CDs) and nanodiamonds (NDs)). These materials were tested on a model system hen egg white lysozyme (HEWL). Using fluorescence measurements and transmission electron microscopy (TEM), the nanoparticles were ranked from the most to the least amyloidogenic as follows: NDs> control> C60> CDs> SWNT. The second subchapter deals with the effect of selected polysaccharides (glycogen (GG), mannan (MAN), phytoglycogen (PG)) and modified GG on amyloid fibril formation. These materials were tested on the HEWL model system,...
System of natural fire risk indicators (verification of various risk assessment procedures occurrence of natural fires) including instructions for the use of the integrated forecast system
Trnka, Miroslav ; Čermák, Petr ; Kudláčková, Lucie ; Balek, Jan ; Semerádová, Daniela ; Brovkina, Olga ; Zemek, František ; Štěpánek, Petr ; Zahradníček, Pavel ; Skalák, Petr ; Bláhová, Monika ; Jurečka, František ; Janouš, Dalibor ; Žalud, Zdeněk ; Marek, Michal V. ; Cienciala, Emil ; Beranová, J. ; Zatloukal, V. ; Albert, J. ; Tumajer, J. ; Možný, M. ; Hájková, L. ; Chuchma, F.
The presented methodology represents an improvement of the currently used system of wildfire monitoring and forecast. Based on extensive testing, it defines two fire weather indices. The method shows how the combination of both indices can lead to robust fire risk estimates. Both indices were uset to generate a forecast of fire weather, but also to quantify th erelationship between the frequency of favorable conditions for the occurrence of natural fires and their observed numbers, in several time steps (from 1 day to the entire season) The methodology has been implemented within the www. portal, where it serves as a tool for operational fire risk forecasting. The text of the methodology therefore contains instructions for using the menthodology therefore contains instructions for using the portal. Great attention is paid in the methodology to the aspect of climate change and estimating the impact of this phenomenon on the frequency of wildfires in the Czech republic.
Recommended adaptation and mitigation measures in risk areas of natural occurrence fires in the light of the changing climate
Trnka, Miroslav ; Čermák, Petr ; Kudláčková, Lucie ; Balek, Jan ; Semerádová, Daniela ; Brovkina, Olga ; Zemek, František ; Štěpánek, Petr ; Zahradníček, Pavel ; Bláhová, Monika ; Cienciala, Emil ; Beranová, J. ; Zatloukal, V. ; Albert, J. ; Tumajer, J. ; Možný, M. ; Hájková, L. ; Chuchma, F.
The methodology formulates graded adaptation and mitigation measures to mitigate fire risk and spread fire in the countryside (forest and agricultural land). To this end, a variant assessment procedure is presented fire risk according to the user's data capabilities. The algorithmization of fire risk in forests is based on forest typology to assess habitats, and adds forest vegetation characteristics. On agricultural Soil agronomic factors include crop type, cover cover, habitat and water characteristics regime. For both territorial categories, the expected impacts of climate change on fire risk are given habitat in the medium term (by 2050). Methodology in conclusion on a case study demonstrates the possibilities of using the model tool FlamMap for the analysis of fire characteristics.
strengthening of circular column subjected to lateral cyclic loading
Mansour, Mohamad ; prof. Ing. Alois Materna, CSc., MBA (referee) ; Fillo,, L´udovít (referee) ; Štěpánek, Petr (advisor)
The presented doctoral thesis deals with the strengthening of circular concrete columns by Fibre Reinforced Polymers (FRP) wraps subjected to lateral cyclic loadings. This research study focuses on examining the use of FRP for retrofitting, improving the performance of circular reinforced concrete columns and developing a design algorithm for circular column strengthening by FRP composite materials based on the analytical study, numerical simulations and the experimental results. Therefore, a design process of strengthening and confinement was presented to predict the behaviour of the concrete columns subjected to lateral cyclic loadings. Simultaneously with the axial force application, the lateral cyclic load was provided in two different ways; first, it was applied under force control test (i.e. same lateral cyclic force pulling in one direction for certain number of cycle’s 1 million cycles), second, it was applied under displacement control - reversed cyclic loading test based on a pattern of progressively increasing displacements. The dissertation also presents a literature review of research studies on the FRP confined concrete, design methodology of FRP jackets in seismic zones and code provisions of Eurocode and ACI. The experimental program was considered to verify the behaviour of confined circular column subjected to lateral cyclic loading. In the conclusions, the behaviour of a cantilever concrete column transversally confined by FRP wraps was investigated and an empirical model for FRP confined concrete subjected to high and low cyclic loadings was proposed and some information on possible future research were provided.
Strengthening of a panel building
Sopúch, Martin ; Girgle, František (referee) ; Štěpánek, Petr (advisor)
This diploma thesis deals with the static assessment of selected parts of the panel building of the former boarding school, for which adaptation to separate housing units and extension of one floor is planned. Upon the planned change of layout, extensions of the original door openings and new openings are proposed. The work assesses the object in its original state with the included unprofessional interference in statics during its use, and the object in the final state with planned modifications of the openings and proposes solutions to secure unsatisfactory areas to suit the new state loads
Zahradníček, Pavel ; Rožnovský, J. ; Štěpánek, Petr ; Farda, Aleš ; Brzezina, J.
Climate assessment should not be limited to just statistical analysis, but also look at relationships in data and its uses in other areas of everyday life. One such area is tourism and recreation, which is also to a great extent influenced by the weather. This paper focuses on the winter season and the related possibilities for tourism. One of the key factors is snow conditions of the particular place. This analysis takes into account the amount of new snow and maximum snow depth and changes in these parameters as a result of the current global climate change. Especially in the last 15 years, years with less snow are more frequent and this is especially seen at highest altitudes of the country. The study also analyzed outputs of climate models with regards to winter season, including calculations of the number of melting days.
Punching Shear of Flat Slabs
Lyčka, Lukáš ; Jaroslav, Halvoník (referee) ; Čajka,, Radim (referee) ; Štěpánek, Petr (advisor)
The use of flat slabs in constructions due to its many functional and economic advantages is wide-spread. Behavior of flat slabs in shear and flexure is a fairly complex problem. Therefore, the punching shear failure belongs to one of the most critical aspects in the design of concrete buildings. Over the last decades several buildings have collapsed due to the failure of the punching shear strength, resulting in loss of lives and financial damages. These disasters revealed gaps in the current (or former) design codes and recommendations. As a part of theoretical framework of the dissertation a method for predicting the punching shear strength of flat slabs was developed. Several experiments on scaled down slabs were conducted in order to verify the proposed method and for optimization of its parameters. Proposed method in development predicts the punching shear for slabs without shear reinforcement according to the EC2 and replaces the area of the shear crack with a system of struts and ties.
Optimized design of reinforcement of concrete cross section
Hudyma, Nazar ; Laníková, Ivana (referee) ; Štěpánek, Petr (advisor)
The subject of this thesis is the optimization of design variables of reinforced concrete cross-section, especially its reinforcement. To solve this problem, it was first necessary to elaborate a search section that discusses various methods and approaches for solving the problem. The research part also includes processing and evaluation of tasks solved by other authors in available literature. For the optimization task, in the following parts both the general formulation and the detailed formulation of the partial parts of the concrete reinforcement structure optimization process are processed. As an example of optimization, a simple beam is chosen, which is subjected to bending moment and normal force one load case, where the example will be divided according to the formulation of both the function and the vector of unknown parameters (variables) defining the exact shape and properties of the reinforced concrete section. The examples will then be tested with regard to the speed of convergence and the degree of deviation between the best solutions found for each optimization algorithm used. At the end there will be a comparison and evaluation of the solution of the given task, as well as a summary of the whole bachelor thesis with reference to another possible direction in the optimization problems focused on reinforced concrete structures. In the appendices there will be a solution of selected examples.
Zahradníček, Pavel ; Rožnovský, J. ; Brzezina, J. ; Štěpánek, Petr ; Farda, Aleš ; Chuchma, F.
Air temperature in winter months and colder half-year is an important factor for wide range of human activities, including recreation. As a result of current climate change, average air temperatures increase in winter as well. This, however, does not mean that there are no frosts. Each winter season can be assessed using several parameters. In this paper we used the sum of effective air temperatures below 0 degrees C and- 5 degrees C. Absolute minimum air temperature was used as an indicator of the extremity of a particular period. Space-time analysis has been performed for both parameters. Air temperatures in winter months are to a large extent influenced by the continentality of the climate. In general, the temperatures in Bohemia rise faster compared to Moravia and the absolute lowest minimum air temperatures are observed in the Western parts of the country. Based on a multiparametric analysis of climate characteristics, the coldest winter and colder half-year was in 1963, in contrast, the mildest winter was in 2007.

National Repository of Grey Literature : 154 records found   1 - 10nextend  jump to record:
See also: similar author names
1 Štěpánek, P.
1 Štěpánek, Pavel
1 Štěpánek, Přemysl
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