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Flatworms (Platyhelmintes: Tricladida) in the Czech Republik
Reslová, Marie ; Juřičková, Lucie (advisor) ; Buchar, Jan (referee)
This work focuses on the freshwater triclads and summarizes information about species occurring in the Czech Republic. Particular chapters concerned generally with taxonomy, anatomy and ecology of triclads; morphology, ecology and occurrence of each species is discussed in detail. 17 triclad species were recorded in the Czech Republic before now, some of them are considered as endemics. The majority of common triclads is determinable according to the head shape, but determination of Dugesia lugubris, D. polychroa a Polycelis nigra, P. tenuis is possible only based on the penis morphology. Some species can be regard as bioindicators, because of their narrow ecological requirements: cold water with high content of O2 - Dugesia gonocephala, Crenobia alpina, Polycelis felina; higher concentration of Ca2+ - D. gonocephala, Phagocata vitta, Planaria torva; oligotrophic standing waters - Polycelis nigra; eutrophic standing waters - Dugesia polychroa, Polycelis tenuis. Species of underground waters and springs are interesting and still unexplored ecological group of triclads.
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Identification of complex modulus using of the Hopkinson Split Pressure Bar.
Buchar, J. ; Trnka, Jan ; Řídký, R.
A split Hopkinson pressure bar procedure was used for non-parametric identificon of complex\nmodulus under conditions of non-equilibrium and axially non-uniform stress Tests were carried out with\naluminium bars and with specimens of composite materials (Low viscosity epoxy resin and Baytube multiwalled\ncarbon nanotubes) and having diameter 15 mm and length 7 mm. The influence of the nanotubes\nconcentration on the dynamic response of given composites was evaluated.
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The Project Selected Leisure Time Activities for Children
Křivánková, Renata ; Buchar, Jaroslav (referee) ; Kysel, Jiří (advisor)
Aim of the thesis was to design leisure time activities for 6-14 years old children under Centre for Sport Activities, Brno University of Technology (CESA VUT). Three sport courses – tennis, athletics and ball games were suggested and thein content as well as propagation outlined. Membership fee was calculated using cost analysis together with analysis of competive environment in similar sport activities in Brno.
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Verification of the Exploitation Possibility of Tensile Strain during the Hopkinson´s Test
Dohnal, Ivo ; Spišák,, Emil (referee) ; Buchar, Jaroslav (referee) ; Forejt, Milan (advisor)
The PhD thesis deals with the possibility of performing dynamic tensile tests. For this purpose, Split Hopkinson Pressure Bar Test (hereinafter SHPBT) is used. The basic construction of SHPBT device is designed to perform dynamic compression tests on materials (metals, plastics, and ceramics). The obtained results are deformation stress – strain and strain rate – strain dependences. SHPBT is capable of testing materials at high strain rates up to 10^2 – 10^3 s-1. It was created a special device for dynamic tensile tests of materials at high strain rates. The created device uses the basic construction of SHPBT. The special device is used for testing flat specimens with 2 mm thickness. It was recognized by the Industrial Property Office of the Czech Republic as a utility model with number 23703. The specimens used for dynamic tensile testing were made of austenitic stainless steel (WNr. 1.4301) with 2 mm thickness. The verification of created device was carried out by numerical simulation. The numerical simulation was performed by ANSYS LS – Dyna software.
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Financial analysis based on financial statements
Buchar, Jiří ; Strouhal, Jiří (advisor) ; Zámečník, Petr (referee)
The goal of this thesis is to analyze company's financial statements to evaluate its overall financial situation between 2008 and 2012. The evaluation has been performed in a context of the economic crisis. This thesis is divided into a theoretical and a practical part. The theoretical part focuses on the term financial analysis and also its tools that are applied in the practical part. The practical part assesses company's financial health through horizontal and vertical analysis, financial ratio analysis, net working capital analysis and bankruptcy models. Furthermore a comparison of the sector values which is designed for the analysis of ratios and spider chart is included in the practical part. You may find the results of the practical part in a following summary which leads to the final evaluation of company's financial health and its prospective future.
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A Split Hopkinson Bar Method for Testing Materials with Low Characteristic Impedance
Buchar, J. ; Řídký, R. ; Drdlová, M. ; Trnka, Jan
A split Hopkinson pressure bar (SHPB) technique has been developed to study dynamic behaviour of materials having low characteristic impedance. To enable better matching of characteristic impedance with a specimen, polymethyl methacrylate (PMMA) bar is used as the output bar. The viscoelastic properties of PMMA are determined in advance through preliminary experiments. In the present SHPB method, the wave analysis of the stress pulses is executed in the frequency domain. Transmitted pulses on the PMMA output bar resulting from a SHPB test are resolved into frequency components by the Fourier transform, and are corrected to be the waveforms at the specimen-bar interfaces. The corrected waveforms have been used for the evaluation of experimental results on the stress pulse transmission and reflection at the interface between elastic (Aluminium) and viscoelastic bars.
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Evaluation of Plate Structure Response to Buried Explosive Charges
Buchar, J. ; Řídký, R. ; Drdlová, M. ; Trnka, Jan
An interactiom of the blast pressure wave after detonation of a burried mine under the multilayer mine protection mounted to the bottom of a vehicle is described in this paper.The main focus was applied to absorbing capability of the multilayer sandwich. Results from numerical simulations were compared with experimental tests. The test procedure is provided according to STANAG 4569/AEP-55 standard with threat level 3B.
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Behaviour of Selected Varieties of Honey at the Impact Loading
Nedomová, Š. ; Trnka, Jan ; Přidal, A. ; Stoklasová, Pavla ; Buchar, J.
Rheological properties of honey are mainly described by its viscosity. This property is particularly critical during storage, handling and processing. The new method of the evaluation of the mechanical behaviour of honey has been designed. This method is based on the evaluation of the honey response to dynamic loading. Dynamic loading has been realized by fall of bar impact. Response function has been represented by the time history of the honey surface displacement. Response of the tested honey varieties have been evaluated both in the time and frequency domain.
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Vliv hospodářských zásahů na změnu v biologické rozmanitosti ve zvláště chráněných územích: Monitorování změn vegetace a populací zvláště chráněných a ohrožených druhů rostlin a živočichů v NPR Novodomské rašeliniště
Okresní muzeum, Chomutov ; Vysoký, Václav ; Tejrovský, Vít ; Němcová, Lenka ; Hajer, Jaromír ; Buchar, Jan ; Ondráček, Čestmír
Cílem průzkumu je sledování změn ve složení vegetace a populace zvláště chráněných a ohrožených druhů vyšších rostlin, mechorostů, obratlovců a vybraných skupin bezobratlých ve vztahu k odvodňování, k působení jelení zvěře a ke změnám globálního charakteru. V roce 2002 byl dokončen průzkum celého rašeliniště. Byly evidovány játrovky, mechy vyšší rostliny. Průzkum bezobratlých byl rozšířen na arachnofaunu. Dále byl průzkum zaměřen na ověření výskytu ptáků zařazených v Příloze I směrnice EU o ptácích. Mimořádná pozornost byla věnována zpracování a vyhodnocení ohrožujících faktorů pro vybrané druhy zvláště chráněných ptáků (chřástal polní, žluna šedá a moták pilich). Zvláštní péče byla věnována zpracování managementových opatření pro tetřívka obecného, žlunu šedou, motáka pilicha, chřástala polního, sýce rousného a bekasinu otavní.
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Hodnocení pevnosti ovoce pomocí měření odezvy při impulzivním zatěžování
Dvořáková, Pavla ; Nedomová, Š. ; Severa, L. ; Trnka, Jan ; Buchar, J.
Dynamic resonance frequency based on dynamic frequency response of excited peach was determined by peach physical properties,such as, peach firmness, peach mass, and day of harvesting. Analysis showed that dominant frequency increased with peach firmness increasing, and dominant frequency decreased with increasing of the peach mass.
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