A brake system of a passenger rail wagons for speeds up to 200 km/h

Bakalářská práce se zabývá návrhem adhezní elektropneumatické kotoučové brzdy pro osobní kolejový vůz pro rychlost do 200 km/h. Rešerše je zaměřena na popis základních principů brzdění železničních vozidel a porovnání čtyř různých brzdových systémů DAKO, jenž jsou vzájemně porovnány v odlišnostech konceptu konstrukce a popsána funkčnost klíčových komponent brzdového systému. Podle zadaných parametrů brzdového systému DAKO pro osobní kolejový vůz pro rychlost do 200 km/h jsou vypočteny základní parametry kotoučové brzdy při rychločinném zabrzdění vozu na požadované zábrzdné vzdálenosti.The bachelor thesis deals with the design of the adhesion electro pneumatic disc brake for passenger rail wagon for speeds up to 200 km/h. The research is focused on a description of basic principles of railway vehicles braking and a comparison of the four different types of DAKO brake systems, which are mutually compared in differences in the construction concept and the functionality of key components of the brake system is described. The basic parameters of the disc brake are calculated according to the set parameters of the DAKO brake system for a passenger rail wagon for speeds of up to 200 km/h, when the vehicle is braked to the required braking distance

Možnosti řešení velkých vrhů selat

The aim of the first experiment was to verify the effectiveness and profitability of providing supplemental feed to piglets. The milk feed mixture of two producers (MFM-1 vs MFM-2) were evaluated (served ad libitum). All piglets were suckled and were fed with the pre-starter feed mixture from the 5th day until the weaning stage. The control group without milk supplements has shown a higher piglet mortality and worse body condition of sows. The usage of milk supplements led to the elimination of the sow body condition loss during the suckling period and reduced feed mixture consumption in sows (P<0.05). The MFM-1 group was found to have a higher consumption of milk supplements, the lowest mortality and the lowest loss of sow body condition (P<0.05). However, from the economic point of view, i.e. the costs on 1 weaned pig, slightly better results have been proven at the MFM-2 milk supplement. In the second experiment sows were divided into 2 groups. In the first group, the piglets were fed with milk substitute and in the second group, nurse sows (15% of the herd) were used. Nurse sows had a longer suckling period and farrowing interval, a slightly lower number of litters per sow per year and by 0.93 lower number weaning piglets per year. Using the milk substitute, generated a higher business profit per year than for nurse sows. However, the fact that nurse sows block the farrowing pen should be taken into account. In case that fewer sows were kept, business profit would be higher.Cílem 1. pokusu bylo ověřit efektivitu a rentabilitu přikrmování selat. Byly hodnocené mléčné směsi dvou výrobců, a to MKS-1 vs. MKS-2 podávané ad libitum. Všechna selata byla kojená a od 5. dne věku do odstavu ve 28 dnech podávaný prestarter. Kontrolní skupina bez přikrmování vykázala vyšší úhyn selat do odstavu a horší kondici prasnic při odstavu. Použití mléčných krmných směsí vedlo k eliminaci ztráty kondice prasnic v období kojení a snížilo spotřebu krmných směsí pro prasnice (P<0,05). U skupiny MKS-1 byla vyšší spotřeba mléčné krmné směsi, nejnižší úhyn a nejmenší ztráta kondice prasnic (P<0,05). Nicméně z hlediska nákladů na 1 odstavené sele, vykázalo mírně lepší výsledky přikrmování mléčnou směsí MKS-2. Ve 2. pokusu byly prasnice rozdělené do 2 skupin. U první skupiny byla selata přikrmovaná mléčnou náhražkou a u druhé skupiny byly využité kojné prasnice, které tvořily 15 % stáda. Kojné prasnice měly delší dobu kojení a délku mezidobí, nepatrně nižší počet vrhů na prasnici za rok a o 0,93 nižší počet dochovaných selat za rok. Při použití mléčné náhražky byl dosažený vyšší podnikatelský zisk za rok než u kojných prasnic. Je však potřeba přihlédnout k tomu, že kojné prasnice blokují porodní kotec. Za předpokladu, že by kojných prasnic bylo chováno méně, podnikatelský zisk by byl vyšší

Fire hazard modulation by long-term dynamics in land cover and dominant forest type in eastern and central Europe

Wildfire occurrence is influenced by climate, vegetation and human activities. A key challenge for understanding the risk of fires is quantifying the mediating effect of vegetation on fire regimes. Here, we explore the relative importance of Holocene land cover, land use, dominant functional forest type, and climate dynamics on biomass burning in temperate and boreo-nemoral regions of central and eastern Europe over the past 12 kyr. We used an extensive data set of Holocene pollen and sedimentary charcoal records, in combination with climate simulations and statistical modelling. Biomass burning was highest during the early Holocene and lowest during the mid-Holocene in all three ecoregions (Atlantic, continental and boreo-nemoral) but was more spatially variable over the past 3–4 kyr. Although climate explained a significant variance in biomass burning during the early Holocene, tree cover was consistently the highest predictor of past biomass burning over the past 8 kyr. In temperate forests, biomass burning was high at ~ 45% tree cover and decreased to a minimum at between 60% and 70% tree cover. In needleleaf-dominated forests, biomass burning was highest at ~60 %–65%tree cover and steeply declined at > 65% tree cover. Biomass burning also increased when arable lands and grasslands reached ~15 %–20 %, although this relationship was variable depending on land use practice via ignition sources, fuel type and quantities. Higher tree cover reduced the amount of solar radiation reaching the forest floor and could provide moister, more wind-protected microclimates underneath canopies, thereby decreasing fuel flammability. Tree cover at which biomass burning increased appears to be driven by warmer and drier summer conditions during the early Holocene and by increasing human influence on land cover during the late Holocene. We suggest that longterm fire hazard may be effectively reduced through land cover management, given that land cover has controlled fire regimes under the dynamic climates of the Holocene

Involvement of the Czech companies in the space exploration

This bachelor thesis is about the space exploration and the space industry in the Czech Republic from the view of companies. First part summarise the importance of space exploration. The second part of my thesis is focused on space exploration and industry in the Czech Republic and involvement of the Czech Republic in ESA. At the conclusion there is analysis of the answers to my questionnaires about space exploration and industry

Entrepreneurship of Czech Small and Medium Enterprises in the Space Industry

Tato diplomová práce je zaměřena na české malé a střední podniky v kosmickém průmyslu. Cílem je prozkoumat a zhodnotit jejich potenciál, zkušenosti a příležitosti. Za tímto účelem byl sestaven komplexní dotazník. Skládá se z kvantitativních i kvalitativních otázek. Práce je rozdělena na dvě části: teoretickou a praktickou. V teoretické části jsou vysvětleny základní pojmy z podnikání a kosmonautiky. Praktická část začíná analýzou světového a českého kosmického průmyslu a pokračuje metodologickou částí a vyhodnocením dotazníku. Závěr této práce je, že české malé a střední podniky jsou schopny uspět a zapojit se do kosmického průmyslu.This thesis is focused on Czech small and medium enterprises in the space industry. The aim is to explore and evaluate their potential, experiences and opportunities. For this purpose, the complex questionnaire was designed. It consist of quantitative and qualitative questions. The thesis is divided into two parts: theoretical and practical. In the theoretical part are explained the basic terms of business and astronautics. The practical part starts with an analysis of an global and Czech space industry and continues by the methodological part and evaluation of questionnaire. The conclusion of this thesis is that Czech small and medium enterprises are able to succeed and participate in the space industry

LED field in the matrix 8x8

The reserach report describes design and implementation issues of LED field with triangular matrix of diodes. LEDs with the narrowest bandwidth and with the largest homogeneity of emitted light cover the widest wavelength bandwidth overall (350 - 1000nm). The proposed equipment is dedicated to multispectral acquisition of paintings

Basal and Activated Calcium Sensitization Mediated by RhoA/Rho Kinase Pathway in Rats with Genetic and Salt Hypertension

Calcium sensitization mediated by RhoA/Rho kinase pathway can be evaluated either in the absence (basal calcium sensitization) or in the presence of endogenous vasoconstrictor systems (activated calcium sensitization). Our aim was to compare basal and activated calcium sensitization in three forms of experimental hypertension with increased sympathetic tone and enhanced calcium entry-spontaneously hypertensive rats (SHR), heterozygous Ren-2 transgenic rats (TGR), and salt hypertensive Dahl rats. Activated calcium sensitization was determined as blood pressure reduction induced by acute administration of Rho kinase inhibitor fasudil in conscious rats with intact sympathetic nervous system (SNS) and renin-angiotensin system (RAS). Basal calcium sensitization was studied as fasudil-dependent difference in blood pressure response to calcium channel opener BAY K8644 in rats subjected to RAS and SNS blockade. Calcium sensitization was also estimated from reduced development of isolated artery contraction by Rho kinase inhibitor Y-27632. Activated calcium sensitization was enhanced in all three hypertensive models (due to the hyperactivity of vasoconstrictor systems). In contrast, basal calcium sensitization was reduced in SHR and TGR relative to their controls, whereas it was augmented in salt-sensitive Dahl rats relative to their salt-resistant controls. Similar differences in calcium sensitization were seen in femoral arteries of SHR and Dahl rats

Basal and Activated Calcium Sensitization Mediated by RhoA/Rho Kinase Pathway in Rats with Genetic and Salt Hypertension

Calcium sensitization mediated by RhoA/Rho kinase pathway can be evaluated either in the absence (basal calcium sensitization) or in the presence of endogenous vasoconstrictor systems (activated calcium sensitization). Our aim was to compare basal and activated calcium sensitization in three forms of experimental hypertension with increased sympathetic tone and enhanced calcium entry—spontaneously hypertensive rats (SHR), heterozygous Ren-2 transgenic rats (TGR), and salt hypertensive Dahl rats. Activated calcium sensitization was determined as blood pressure reduction induced by acute administration of Rho kinase inhibitor fasudil in conscious rats with intact sympathetic nervous system (SNS) and renin-angiotensin system (RAS). Basal calcium sensitization was studied as fasudil-dependent difference in blood pressure response to calcium channel opener BAY K8644 in rats subjected to RAS and SNS blockade. Calcium sensitization was also estimated from reduced development of isolated artery contraction by Rho kinase inhibitor Y-27632. Activated calcium sensitization was enhanced in all three hypertensive models (due to the hyperactivity of vasoconstrictor systems). In contrast, basal calcium sensitization was reduced in SHR and TGR relative to their controls, whereas it was augmented in salt-sensitive Dahl rats relative to their salt-resistant controls. Similar differences in calcium sensitization were seen in femoral arteries of SHR and Dahl rats