ON EFFICIENT OPERATIONAL CONCEPT OF FUTURE HIGH-SPEED RAILWAY IN THE CZECH REPUBLIC

The aim of this paper is to elaborate a layout of the first operational concept of Rapid Services with 1 hour system travel time between Praha and Brno. Two basic methods are used – Integrated Periodic Timetable (periodic rendezvous of all services in IPT-nodes) and Operational Concept Economy Approach, as defined below by the author. In this paper, three recent high-speed railway concepts for the future so-called Rapid Services network of the Czech Republic are followed-up. The first one is an operational traffic planning study by Kalcík, Janoš et al. on behalf of Czech Ministry of Transport from 2010. The second one is the high-speed railway promoting book High Speed Rail Even in the Czech Republic by Šlegr et al. from 2012, with likely the most detailed concept of Rapid Services network. The third one is a paper on progress of the official spatial-technical studies for some future Czech high-speed lines by Šulc from 2014. The importance of achievement of 1 hour travel time between the largest agglomerations is briefly presented. The presented methodological approach, although soft and manager-oriented, comprises some firm principles: segmentation of high-speed train offer, so that more expensive rolling stock is not wasted by operation on long conventional line sections, consideration of system travel times for efficient rolling stock circuit, restriction of need for links from high-speed to conventional lines, and utilization of high-speed lines as a "rail highway". This approach is intended to be particularized iteratively, with every application. So, in this paper, first version of Operational Concept Economy Approach is introduced. The key idea is that passengers should be offered such travel times and service intervals (headways) and such number of direct services, which are adequate to their potential demand, but as much synergistic effect as possible should be strived to be achieved for every proposed construction (new or modernized one). Such approach goes towards economic efficiency, which is crucial indicator for political decision necessary for building, let alone EU co-funding of the construction. Experience shows that in many Czech feasibility studies, achievement of sufficient economic efficiency was the most complicated part of the study. Results show that an efficient operational concept can be designed not at the expense of runtimes between the largest cities

Differentiated Estimates of Valuation Multipliers based on Price-to-Book Ratio for the Czech Brewing Industry

This article focuses on the differentiated estimations of industry multipliers in relation to Price-Book Value ratio (P/BV) with applying for the Czech brewing industry. Differentiation of estimates brings better approximation of these sector-wide multipliers to the defined groups companies within the given markets and thus increases the accuracy of the method of relative business valuation. Due to the absence of market data on privately held companies, the market value was assessed using the DCF method, while the book value was taken from the enterprise's accounts. The assumption of the linearity of the market-book value relationship for the subsequent calculations and differentiation of P/BV estimations was verified using regression analysis. The differentiation of P/BV ratio was made according to the size of entities, but mainly based on equality of market and book value, respectively according to the equality P/BV = 1. Then our results were supplemented by the calculation of industry P/BV ratio using P/EAT ratio and ROE decomposition. Using this additional method, the brewing industry was compared with other relevant industries in the Czech Republic.O

The Impact of Different Manufacturing Technologies and Thermal Processing of Groove Profiles on the Service Life of Ball Screws

Tato diplomová práce pojednává o měření životnosti kuličkových šroubů. Práce je rozdělena na teoretickou a praktickou část. V teoretické části jsou popsány tři základní metody výroby kuličkových šroubů – válcování, rotační okružování a broušení. Následně je popsáno tepelné zpracování kuličkového šroubu, a to indukční a laserové kalení. Praktická část je věnována provedení testů životnosti kuličkových šroubů a jejich vyhodnocení. Testy byly provedeny na dvou dvojicích kuličkových šroubů. První dvojice byla vyrobena odlišnou metodou výroby (okružováním a broušením) a následně indukčně zakalena. Druhá dvojice byla vyrobena broušením a následné tepelné zpracování bylo u každého šroubu odlišné (laserové a indukční kalení). Výsledky testů jsou následně vyhodnoceny dle mezinárodních standardů.The aim of this thesis is ball screw service life measurement. Text is divided on two major parts, theoretical one and practical one. Theoretical part describes three basic methods of ball screws manufacturing – rolling, whirling and grinding. Subsequently, methods of heat treatment (inductive and laser hardening) are mentioned. Practical part is devoted to ball screw service life testing and evaluation of results. Tests were carried out on two sets of two ball screws. First set was manufactured by whirling and grinding followed by inductive hardening. Second set was manufactured by grinding followed by inductive hardening in one case and laser hardening in the second one. Test results were evaluated according to international standards.

High-speed rail network and periodic timetable: a comparative analysis of operational concepts

This paper compares chosen European high-speed railway (HS) networks in terms of their offer of HS passenger service. The criteria chosen for comparison are network topology, degree of service periodicity and degree of coordination between subsequent services. Only services with HS trains are taken into account. As a result, each examined network is classified according to prevailing approach to passenger service – either Line/Service (LS) Approach, where transfer connections are in general not anticipated, or Network (N) approach, with regular (mostly periodic) public transport lines and periodic transfer connections between them.The comparative analysis has shown that geography had crucial impact not only on national (or regional) HS line network, but on the HS operational concept as well.On trunk HS lines, which connect most populated agglomerations in particular country, there is always – at least during peak times – some form of periodic service, despite compulsory seat reservation (except state-owned carriers in Austria and Germany).Half of analyzed networks can be characterized by N approach – at least on trunk HS lines or within central "core" part of HS network.For Czech HS network, authors recommend to define a core network with application of Integrated Periodic Timetable

Measurement of roughness of the laser cutting edge

Tato bakalářská práce pojednává o technologii laserového dělení materiálů. Práce je rozdělena na teoretickou a praktickou část. V teoretické části je popsán základní princip, funkce, rozdělení a jednotlivé druhy laserů. Následují popisy jednotlivých využití laserů ve strojírenském průmyslu, větší pozornost je věnována laserovému dělení materiálů. V experimentální části je uvedena metodika měření drsnosti zkušebních vzorků, které byly nařezány z korozivzdorné oceli X5CrNi18-10, následné vyhodnocení parametrů drsnosti a porovnání s normou ČSN EN ISO 9013.This bachelor thesis deals with laser cutting technology. The thesis is divided into theoretical and practical part. In the theoretical part is described the basic principle and function of the laser and the distribution of different types of lasers. Descriptions of each use of lasers in the engineering industry follow, more attention is mainly devoted to laser cutting. In the experimental part is presented a methodology to measure the roughness of the test samples which were cut from stainless steel X5CrNi18-10, the subsequent evaluation of the roughness parameters and comparison with the norm ČSN EN ISO 9013.

NETGRAPH – AN EFFICIENT TOOL FOR PERIODIC TIMETABLING AND CAPACITY PLANNING

A netgraph is a graphical representation of a periodic timetable concept for given spatial or modal scope. It adds a third dimension to the network plan – time. Despite no strictly prescribed rules, a common practice notation has been settled over time. The authors propose an extension of a netgraph for planning of periodic railway capacity and operation, including related notation rules

The impact of the heat accumulation on energy efficiency of building

It is still a lingering practice to classify energy demands of buildings on the basis of thermal insulation properties of th building envelope, although, more aspects, which cannot be ignored, enters to the evaluation. It is necessary to perfor the calculation of the impact of each aspect on the basis on thermal response of the room, which varies primarily by th thermal storage properties of construction materials used. This article deals with the possibility of reducing energy use i buildings by knowledge of the thermal accumulation properties of the mass of the structures. This knowledge create appropriate premises for rational determination of the required thermal conditions for the internal environment unde which are the parameters of the heating systems, heat sources, methods of regulation and optimization of the total hea consumption taken into consideration

NETGRAPH – AN EFFICIENT TOOL FOR PERIODIC TIMETABLING AND CAPACITY PLANNING

A netgraph is a graphical representation of a periodic timetable concept for given spatial or modal scope. It adds a third dimension to the network plan – time. Despite no strictly prescribed rules, a common practice notation has been settled over time. The authors propose an extension of a netgraph for planning of periodic railway capacity and operation, including related notation rules

A Proposal to open a front hood a ŠKODA OCTAVIA car with the help of a gas spring

Práce se zabývá návrhem mechanismu pro otvírání kapoty motorového prostoru automobilu pomocí plynové vzpěry. Shrnuje všechny teoretické informace potřebné k započetí návrhu a podává přehled postupu prací při umisťování plynové vzpěry pod kapotu vozu Škoda Octavia