Risk assessment design margin of process and power equipment

Předložená závěrečná práce se zabývá popisem a aplikací metodiky určování návrhových rezerv u procesních a energetických zařízení na základě vyhodnocování jejich významnosti pro provoz. Předmětná metodika je teoreticky rozebrána, uvedena do kontextu návrhové praxe a následně demonstrována na příkladech. Zvýšená pozornost je v práci věnována aspektům tepelného návrhu zařízení na výměnu tepla, jakožto nezbytnému základu metodiky.This work is devoted to description of methodology of determining process and power equipment design margins, which is based on assessment of a relative process importance of the equipment in question. The methodology is theoretically analysed, brought into context of common design practice and demonstrated on actual cases. Substantial part of this work analyses heat transfer in general as a base of heat exchanger design process.

E-shop design and implementation of company

Diplomová práce charakterizuje a analyzuje obchodní společnost. Obsahuje návrh řešení vyplývajících z analýzy, řešení implementačních problémů a je projektovým nástrojem pro zlepšení budoucího postavení firmy na trhu, a to pomocí elektronického obchodu a jeho prostředků. Dále popisuje ekonomické zhodnocení návrhu elektronického obchodu a jeho implementaci ve společnosti.This diploma work characterizes and analyzes the business company. It contains method of solving problems, consequent on the analysis, solving implementation problems and it is project tools for improve future position of company on market by means of electronic market. For further, it is describe economics analysis of design e-shop and it is implementation in chosen company.

Uporaba abrazivnog vodenog mlaza za mjerenje zaostalih naprezanja u željezničkim kotačima

The paper provides a general introduction to methods of measurement of residual stresses on railway wheels. Determination of residual stress distribution is necessary for the prediction of wheel service life and possible catastrophic failure. Therefore experimental section is devoted to residual stress measurement using strain gauges according to standard EN 13262 + A1. During measurement, several segments of tested wheel were cut by abrasive water jet to detect changes of residual stresses on specified places. It was found that abrasive water jet technology can cut wheel segments faster, more accurately and with negligible mechanical and thermal load compared to mechanical cutting by band saw. Therefore the use of abrasive water jet is recommended for the measurement of residual stresses in railway wheels.The paper provides a general introduction to methods of measurement of residual stresses on railway wheels. Determination of residual stress distribution is necessary for the prediction of wheel service life and possible catastrophic failure. Therefore experimental section is devoted to residual stress measurement using strain gauges according to standard EN 13262 + A1. During measurement, several segments of tested wheel were cut by abrasive water jet to detect changes of residual stresses on specified places. It was found that abrasive water jet technology can cut wheel segments faster, more accurately and with negligible mechanical and thermal load compared to mechanical cutting by band saw. Therefore the use of abrasive water jet is recommended for the measurement of residual stresses in railway wheels.Web of Science19239038

Verification of the model for predicting the properties of the combustion process

Tato práce se zabývá detailním rozborem již dříve vytvořeného výpočtového modelu pro predikci charakteristických parametrů spalovacího procesu ve zkušební spalovací komoře. Odstraňuje nedostatky modelu, které byly rozborem nalezeny, zpřesňuje jej, a následně aplikuje na celkem 11 případů uskutečněných spalovacích zkoušek pro různé pracovní podmínky a paliva. Získaná data konfrontuje s daty zjištěnými v průběhu spalovacích zkoušek, a následně vyhodnocuje přesnost modelu, přičemž hlavním porovnávaným parametrem je velikost měrných tepelných toků do stěn spalovací komory po její délce. Na základě zjištěné přesnosti a objevených nedostatků vyhodnocuje vypovídající možnosti modelu a prezentuje možnosti jeho dalších úprav a možného využití.This work thoroughly analyzes a previously created computational model for predicting characteristic properties of the combustion process in an experimental combustion chamber. Any found shortcomings of the original model are removed and the model is further improved prior to its application on 11 real cases of combustion tests performed at various conditions and with various fuels. Data provided by the model are confronted with the data obtained during the combustion tests and the model accuracy is evaluated, based on local heat flux along the length of the combustion chamber. Finally, the overall usefulness of the model is determined by the means of evaluating the acquired accuracy values, and further possibilities of model improvement and use are presented.

Optimalization of hanger design in petrochemical industry

Diplomová práce, „Optimalizace tvaru háku v pecích petrochemického průmyslu“, popisuje postup a prostředky, jež vedou k vhodnějšímu tvaru háků v rozličných případech. Práce zároveň popisuje různá úskalí, která je nutná u navrhování háků zohlednit. Jsou popsány různé tvary háků, které jsou posuzovány v širších souvislostech z technického hlediska. Je vybrán jeden typ háku, na kterém je postup optimalizace názorně předveden.Master’s thesis, „Optimization of hanger design in petrochemical industry heaters”, describes a procedure and means, leading to better hanger design in various cases. The thesis describes several problems which are necessary to be solved in hanger design. Technical expertise is executed on hangers of various designs. The procedure of optimization is shown on one chosen hanger design.

Komentovaný seznam měkkýšů zjištěných ve volné přírodě České a Slovenské republiky

In this paper we provide a new list of all the mollusc species recorded outdoors in the Czech and Slovak Republics. This work is a supplement of the Ložek’s key on molluscs of the former Czechoslovakia. For the species recorded after the publishing of the book, publications of their first records in the Czech and Slovak Republics are given. Species which are either not included in this Ložek’s book or whose current taxonomical status highly differs from that published in the book are supplied with Czech commentaries, photographs of their shells or bodies, and drawings of important identification characters. This material is aimed at Czech and Slovak malacologists to provide information, missing or scattered in the literature, on currently known mollusc fauna of the Czech and Slovak Republics. The Ložek’s book and this supplement should provide necessary information on identification, ecology and also distribution of all mollusc species currently known from the Czech and Slovak Republics. If the species names used in this paper differ from the ones used in the Ložek’s book, we mention both. So far 247 species of molluscs, including 219 species of gastropods (50 aquatic and 169 terrestrial) and 28 species of bivalves, have been found outdoors in the Czech Republic. The fauna of Slovakia comprises 247 species, including 219 gastropods (51 aquatic and 168 terrestrial) and 28 bivalves. Altogether 282 species occur in the Czech Republic and Slovakia, 212 of them being common to both countries

The first record of Corbicula fluminea (O. F. Müller, 1774) in Moravia (SE Czech Republic)

Corbicula fluminea, an invasive bivalve of SE Asian origin, has been recorded in the Morava River in Moravia (SE Czech Republic, Danube River basin) for the first time in 2018

Radiation in Bythinella Moquin-Tandon,1856 (Mollusca : Gastropoda : Rissooidea) in the Balkans

61 sequences of cytochrome oxidase subunit 1 (COI), 570 bp long, from Central Europe (8), Slovenia (2), and from the Balkans (51: 6 from, Romania, 15 from Greece, 15 from Bulgaria, 6 from Serbia, and 9 from Montenegro), 33 of them new, together with 61 sequences of the ribosomal 18S, 450 bp long, all of them new, were analysed to infer the pattern of radiation of Bythinella in the Balkans. Thirty two nominal taxa of Bythinella (22 nominal species: B. austriaca, B. calimanica, B. charpentieri, B. compressa, B. dacica, B. dispersa, B. grossui, B. hansboetersi, B. luteola, B. micherdzinskii, B. molcsanyi, B. nonveilleri, B. pannonica, B. pesterica, B. radomani, B. rhodopensis, B. robiciana, B. schmidti, B. slaveyae, B. srednogorica, B. taraensis and B. viseuiana; one nominal subspecies: B. austriaca ehrmanni; and nine Greek species not yet described) were included, represented mostly by paratypes or at least topotypes, collected at 31 Balkan localities. The phylogeny, inferred on the combined data set with the ML approach, showed two large clades, although they were weakly supported. One of them comprised the Romanian and Montenegro populations, and one Serbian population, the other (less genetically diversified) consisted of one Serbian and all the Bulgarian/Greek populations. The origin of those two clades was dated, with the external data, to be more than 4.341±0753 MYA old, thus its origin was assigned to isolation by the Dacic Basin (part of Paratethys). All the Bulgarian populations presumably belong to one species, which may be assigned to the recent recolonisation of this territory from the south

RELATIONSHIPS BETWEEN BROWSING DAMAGE AND THE SPECIES DOMINANCE BY THE HIGHLY FOOD-ATTRACTIVE AND LESS FOOD-ATTRACTIVE TREES

Abstract ČERMÁK, P., BERANOVÁ, P., ORÁLKOVÁ, J., HORSÁK, P., PLŠEK, J.: Relationships between browsing damage and the species dominance by the highly food-attractive and less food-attractive trees. Acta univ. agric. et silvic. Mendel. Brun., 2011, LIX, No. 1, pp. 29-36 The paper analyses data on the browsing damage to Acer pseudoplatanus, Carpinus betulus, Fraxinus excelsior, Quercus spp., Tilia cordata and Fagus sylvatica. Field research was carried out in the period 2007-2010 and analysed data came from 33 transects at 10 localities with the various abundance of game in the CR (everywhere Capreolus capreolus, on several plots also Cervus elaphus, Ovis musimon or Dama dama). Trees were monitored up to a height of 150 cm in natural regeneration under stands and in plantations and the occurrence was noted of new browsing damage. Diff erences between the percentage of damaged individuals of the given species of a food-attractive species (A. p., C. b., F. e.) and the percentage of damaged individuals of all tree species on a transect as well as the proportion of these parameters correlate negatively with the given species dominance and thus, they appear to be suitable parameters for the analysis of relationships between the damage intensity and dominance. The higher the percentage proportions of highly food-attractive species and the lower the percentage of less-attractive species, the lower the relative intensity of damage to highly food-attractive species. At the same time, the higher the percentage proportion of highly food-attractive species and the lower the percentage of less-attractive species then the lower a diff erence between damage to less food-attractive species and all species. browsing, dominance, highly food-attractive species, less food-attractive species, correlation The attractiveness of tree species for ruminant consumers is highly species-specifi c, however, dama ge to particular tree species markedly diff ers at various localities, namely in absolute values and in relation to other species. Generally, the species structure of advance regeneration and the species rareness are the most mentioned factors aff ecting the preference of a species by browsing animals. That is, tree species are usually more intensively searched if they are in combination with less attractive species and relative damage is o en in relation to the species relative abundance or its dominance. In some cases, the damage increases with the relative proportion of a species, in other cases increases with the decreasing proportion of these species in advance growth both polarities of relationships being interpretabl