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Der Versuch, den Radverschleiß von Zügen vorherzusagen, ist bis heute keine leichte Aufgabe. Mit den von den ÖBB zur Verfügung gestellten Daten wird in dieser Arbeit versucht, ein neuronales Netzwerk zu bauen, welches den Verschleiß der Räder auf einer bestimmten Strecke genau vorhersagen kann. Mit den gegebenen Daten wurden bereits Regressionsmodelle erstellt, die genau dieses Problem angehen. Es wird davon ausgegangen, dass diese Modelle bereits die beste Vorhersagekraft haben. Nichtsdestotrotz wurden große Anstrengungen unternommen, um ein Netzwerk zu entwickeln, das diese Modelle zu übertreffen versucht. Ein endgültiges neuronales Netz wird in Python mit TensorFlow und Keras erstellt. Es verwendet einen versteckten, einen Dropout- und zwei Batch-Normalisierungs-Layer. Es wurden insgesamt 213 Testläufe durchgeführt. Mit jedem Test wurden der Scheduler und die Netzwerkkonfiguration verbessert. Vier ähnliche Forschungsarbeiten wurden als Referenzpunkte für die Konstruktion verwendet. Bestimmte Parameter, wie z. B. die Radkranzbreite, kamen der Fehlerspanne der Regressionsmodelle sehr nahe. Sie erreichten oder überschritten sie jedoch zu keinem Zeitpunkt. Dies bestätigt die Hypothese, dass es mit den gegebenen Daten nicht möglich ist, eine bessere Vorhersagekraft zu erzielen, als die Regressionsmodelle erreichten. Mit qualitativ hochwertigeren Daten, die ein breiteres Spektrum von Variablen umfassen (wie Wetter, Temperatur, Gleisbedingungen, Fahrgastanzahl usw.), könnten wahrscheinlich bessere Ergebnisse erzielt werden. Eine andere Interpretation ist, dass sich der Einsatz anderer Modelle (wie z. B. Entscheidungsbäume) für die Vorhersage des Verschleißes mit den vorhandenen Daten besser eignen könnte. Trying to predict wheel wear on trains is still no easy task to date. With the provided data from ÖBB, this work tries to build a neural network, that can accurately predict the wear of the wheels on a given track. With the given data, regression models have already been created, that tackle this exact problem. It is hypothesized, that these models already have the best prediction power. Nonetheless, great effort has been put into creating a network, that tried to surpass them. A final neural network is created in Python with TensorFlow and Keras. It utilizes one hidden, one drop out and two batch normalization layers. There were 213 total test runs performed. With each test, the scheduler and network configuration was improved upon. Four similar research papers were used as reference points for the construction. Certain parameters, such as the wheel rim width, came really close to the error margin of the regression models. Yet, they never reached or exceeded them. This proves the hypotheses that with the given data, it is not possible to get better prediction power, than the regression models achieved. With more high quality data, that encapsulates a wider range of variables (such as the weather, temperature, rail conditions, passenger number, etc.), it would probably be possible to achieve better results. Another interpretation is that the deployment of different model (such as decision trees) could lend themselves more useful for prediction wear with the existing data. submitted by: Jan Mühlbacher Bachelorarbeit FH JOANNEUM 2022

The possibility of utilization of wind energy for electric generation is known. Integration of renewable energy resources in a distribution system poses the necessity of a considerable change in the coordination procedure. This article talks about current situation of renewable energy resources in the world from the point of view of wind energy. It summarizes and describes about some of the technical current and further problems that the development of this energy is facting.

Although the number of nuclear scientists and technologist may appear to be sufficient today in some countries, there are indicators, e. g. declining university enrollment, changing industry personnel profiles, dilution of university course content, and high retirement expectation, that future expertise is a risk. The need to preserve, enhance or strengthen nuclear knowledge is worldwide recognized since a couple of years. Today, the priorities of the scientific community regarding basic research lie elsewhere than in nuclear sciences. Many of the highly competent engineers and, who helped create the present nuclear industry, and its regulatory structure, are approaching retirement age. These competence issues need to be addressed at Community level and a well designed Community research and training program should play a role is a more important than ever before. Czech Nuclear Education Network CENEN is a voluntary academic association of educational institution offering teaching and training in the area of Nuclear Engineering. It is striving to develop and maintain a high standard of Czech nuclear education and to reach its integration into the all-European context. CENEN was established in Prague on May 2005, in the framework program the European Commission supports the European Nuclear Engineering Network ENEN.

This paper deals with the evaluation of renewable and alternative energy sources network interconnection and their impacts on the operation and stability of electrical network. The article shows the dependence of the voltage level magnitude in the point of common connection on the power factor of the renewable energy sources generator. The following part analyses, how the short-term power variation of the power plants (wind and photovoltaic) regarding the weather changes cause the voltage variations according to the generator operational mode. These variations negatively influence the distribution network operation and the power quality. The dynamic variations were simulated by the NEPLAN software. In conclusion the feasibility of the plant interconnection is evaluated respecting other important factors (flicker, ripple control signal damping, harmonic voltages content, protective relays function).

This article describes how can be shielding effectiveness (SE) measured and calculated. There are mentioned systems for SE measuring and possibility of their usage in our laboratory. Then there are introduced some factors influencing shielding such as holes and gaps in cover or cavity resonance.

This paper is focused on problematic of the utilization of the heat pumps. Its first part is dedicated to this method of the heating generally. The principle of the heat pumps, their basic part and their division are presented here. Then the heat pump market in the Czech Republic is analyzed very shortly in the second part. Because great number of the companies is engaged in this source of the heat, I focused only on the organizations which deal with this heating. The next part of the work is concerned with the individual installations or the operation evaluation of heat pumps in the Plzeň region and the region of Karlovy Vary. This is the subject of the third part in which I worked out the overview of ascertained heat pump installations in the commercial buildings in these two regions and of the fourth part where I evaluated the heat pump operation in one selected building. Problems of the heating using heat pumps becomes more and more topical in the connection with the increasing prices of the energies and thus in the last part of the work I deal with some of the heat pumps of the future and their utilization.

This paper deals with possible algorithms, which may ensure numerical stability of Newton-Raphson method in load flow analysis. Although the Newton-Raphson method is frequently used, it may have difficulties to obtain convergence. Oscillations, divergence or even convergence to unfeasible solutions may appear using traditional procedures. Therefore, various techniques (such as update truncation, factor relaxation, etc.) can be broadly employed to increase the reliability of the results obtained. The aim of this paper is to find the best available stability algorithm providing solutions with minimum number of iterations and lowest CPU time requirements.

This article deals with radiant heating systems. It also deals with the heating of wall-mounted radiant panels, ceiling-mounted radiant panels and radiant floor heating. Advantages of radiant floor heating are showed as well. Various types of radiant floor heating are mentioned at the end.

This paper describes the opportunity in the energy generation and energy use by the Pilsen heat power station and their positive impact on the environment by the biomass integration for energy generation. Building of this complex took 20 month. It was the equipment, which makes possible to produce the energy from utilization of the biomass. For these reasons, environmental impact is a factor of increasing relevance and importance that conditions the present operation and development of this system and will indisputably have an even more intense effect on the industry in the future.

This paper deals with the form of renewable energy - solar energy through photovoltaic cells and modules. Materials presently used for photovoltaic include monocrystalline silicon, polycrystalline silicon, microcrystalline silicon, cadmium telluride, and copper indium selenide/sulfide. Due to the growing demand for renewable energy sources, the manufacture of solar cells and photovoltaic arrays has advanced dramatically in recent years.

The main purpose of this paper is to analyze measured data from photovoltaic system placed on the building of Faculty of Electrical Engineering in Pilsen, to figure out optimal inclination of installation, to evaluate measured and calculated characteristics and to set possible way of research.

This paper deals with the essential function of generator circuit breaker in power plant. The aim of the paper is to analyse very demanding current and voltage conditions which are directly influencing the reliability of energy generating process. The development in the field of circuit breakers has reached nowadays status of superiority of SF6 based circuit breakers. There are analysed performance capabilities of possible generator circuit breakers for perspective nuclear power plant in the Czech Republic.

This work deals with electromagnetic interference high-voltage equipment. Are described sources of interference and their effects. Furthermore, there are practical ways to describe constraints HF noise.

This paper describes power loss factor measuring of turbogenerator bars. Then it focuses in influence of measuring electrode setting to power loss factor magnitude. It was tested 16 measuring electrode settings. Measurements showed weaknesses in certain methodologies and therefore were proposed changes in methodology.

This paper deals with support and ancillary services which are provided by CEPS a. s. Czech republic System service ensured a balance between production and consumption of electricity and the quality and control of the entire electricity system. The aim of the paper is to create a small overview about this sphere.

There is an extraordinary development and faith nowadays in the field of photovoltaic technology, due to its parameters. This kind of technology is perfect to use in the conditions of an isolated operation network, because of its independence from power grid, usage of primary fuels or other means to power it. In principle, the only thing you really need is a sun shine.

This article deals with the renewable energy sources. More concretely it deals with the solar energy and photovoltaic cells. The article describes inclusive flash history and distribution of solar devices. The principle of photovoltaic cell function and constructions is mentioned marginally.

This paper describes the opportunity in the Pilsen region to build complex for waste incinerator. The new waste incinerator in Chotíkov could by have positive impact on the environment in this region. Building of this complex took a few months. It will be the equipment, which makes possible to produce also the energy from utilization of the waste. For these reasons, environmental impact is a factor of increasing relevance and importance that conditions the present operation and development of this system and will indisputably have an even more intense effect on the industry in the future.

This paper deals with new technology in industrial heating processes – magnetic heating of billets. The aim of the paper is to explain the principle of this technology, construction of the industrial device and differences between classical induction heating and magnetic heating of billets. Further I want to describe the advantages of magnetic billet heating.

Solar energy refers primarily to the use of solar radiation for practical ends. However, all renewable energies, other than geothermal and tidal, derive their energy from the sun. Solar technologies are broadly characterized as either passive or active depending on the way they capture, convert and distribute sunlight. Active solar techniques use photovoltaic panels, pumps, and fans to convert sunlight into useful outputs. Passive solar techniques include selecting materials with favorable thermal properties, designing spaces that naturally circulate air, and referencing the position of a building to the Sun. Active solar technologies increase the supply of energy and are considered supply side technologies, while passive solar technologies reduce the need for alternate resources and are generally considered demand side technologies.

This paper deals with new methods of measurement in an electrical grid. The aim of the paper is to explain the way of distant measuring and shows the hardware solutions. AMR & AMI are very important parts of the smart grid concept.

This paper deals with mathematical modelling of doubly-fed asynchronous generator for wind power plant by the space phasors method. In this paper, the basic principles and characteristics of the system are briefly described, the mathematical description of this machine is shown, the computer model in the Matlab/Simulink program is presented and its function is briefly explained. At the end, possibilities of its next improvement are also mentioned.

This paper deals with a latent heat storage system using Phase Change Materials (PCM) as an effective way of storing thermal energy (solar energy, off-peak electricity, industrial waste heat). It has the advantages of high storage density and the isothermal nature of the storage process. This article will show to find a suitable PCM for various purposes a suitable heat exchanger with ways to enhance the heat transfer, and it will show a variety of designs to store the heat using PCMs for different applications, i.e. space heating and cooling, solar cooking, greenhouses, solar water heating and waste heat recovery systems.

According to the European Environment Agency, the use of biomass for clean energy generation in EU could be significantly increased in the next decades. There are a wide variety of biomass resources, including tree and grass crops and forestry, agricultural, and urban wastes. This paper deals with possibilities of generating energy from biomass resources in Slovakia.

This paper deals with the use of geothermal resources for production of electricity energy. Next is technologies of changes geothermal energy into electrical energy, future of geothermal energy and advantages and disadvantages of geothermal energy.

This paper deals about hydro power plants in Slovak Republic. Hydro power plants are significant part of Slovakian power system. They are used to generation peak load, frequency regulation etc.. Hydropotential in Slovakia is used at 51%. Hydro power plants produce 21% of electricity every year.

Problems of the photovoltaic cells becomes more and more topical in connection with sharply rising prices of the electrical energy and thus the new technology of solar cells produce are invented. This paper is focused on problematic of one of the new trends in the photovoltaic cells sphere – on the Sliver technology. This is the monocrystalline silicon technology which reduce the silicon usage and thereby the cost of the photovoltaic cells. The technology could have decreasing the silicon feedstock requirements to 1 tonne per MW. On top Sliver cells are great at high performances characteristic, e.g. high efficiency, high open circuit voltage, near lambertian light trapping, very good tolerance of varying material quality, etc. The first part of this paper is dedicated to the Sliver technology generally. The concept of the Sliver photovoltaic cells, texturing method, most important Sliver cell design and IV curve are presented here among others. In the second part I deal with the Sliver modules. There are described the principle of the modules, most important performance, e.g. low operation temperature, low temperature coefficient, high energy yield, light high performance, etc.

The nuclear power plants use for supply of onsite power system the normal, standby and emergency sources. The subject of my report is the optimalization of winding connection of lower voltage of auxiliary normal and standby transformers. The suppliers use the delta connection or star connection connected to earth through high – ohmic impedance.

This paper deals with pumped storage hydro power plants in the Slovak Republic. The aim of the paper is describe pumped storage hydro power plants, which are important to operate power system. They're a way of storing energy so that we can release it quickly when we need it. If power stations don't generate more power immediately, there'll be power cuts around the country - traffic lights will go out, causing accidents, and all sorts of other trouble will occur.

Problems of heat pumps are kept under constant review. All from us are aware that energy prices are growing from one year to another. In this context many of us have found themselves the challenge to growing production costs and hot water heating in the house, apartment or other object. Exist a number of solutions but they always depend of suitability of their use in what geographic area and climate zone we live. Experts around the world are for a long time dealing with the idea of alternative solutions to the rational reduction of heat energy. The costs of heating are 15,000 kWh of heat energy for classical house with an area of 200 m2 of heating space. The next part is the energy needed for cooking, lighting and it is around 3500 kWh. Based on these facts have been developed a number of interesting technologies, such as: solar collectors, low temperature condensing boilers, wood-gas stoves, fireplace heat exchangers etc. However, neither of these technologies used as much energy from renewable natural resources as a heat pump. Technology which receives heat (without combustion) of natural resources is called a heat pump.

Biomass power, derived from the burning of plant matter, raises more serious environmental issues than any other renewable resource except hydropower. Combustion of biomass and biomass-derived fuels produces air pollution; beyond this, there are concerns about the impacts of using land to grow energy crops. How serious these impacts are will depend on how carefully the resource is managed. The picture is further complicated because there is no single biomass technology, but rather a wide variety of production and conversion methods, each with different environmental impacts.

This paper deals with evolution and potention of wind energy in Europe. Europe is today in the centre of an energy revolution that will impact the way we think about electricity as fundamentally as did the emergence of coal in the past. It is driven by the desire of European peoples to have cleaner, safer, more secure power to supply their needs, in contrast to the constrained fossil fuels of yesterday.

The wing power used for power generation is a still a new technology especially in the Czech Republic. But this kind of power has today the highest potential from all renewable sources for power generation.

This paper deals with the issue of combustion of biomass in the existing fossil fuel power stations in the Czech Republic. The first parts are focused on ecological and social advantages resulting from development of renewable sources in energetic. In the next part, the influence of the state support on the combustion of biomass for generation of electric power is considered. The calculation in the last part of this paper demonstrates economic efficiency of biomass combustion in midsized source of power.

This paper presents a review of some techniques for islanding detection, especially by using inverter based DG applications and it also focuses on several islanding detection methods for a single-phase current-control voltage inverter working with a PV system connected into the grid. It is deliberated a single-phase inverter with maximum power of 5 kW. Islanding detection methods are investigated, simulated and evaluated in MATLAB / SIMULINK.

This article deals with reducing the cost of heating using infra heat. Infra heating is produced a very pleasant climate and has many advantages opposite traditional heating.

The heat pump was imagined by Lord Kelvin in 1852 and developed by Peter Ritter von Rittinger in 1855. After experimenting with a freezer, Robert C. Webber built the first direct exchange groundsource heat pump in the late 1940s. [11] The first successful commercial project was installed in the Commonwealth Building (Portland, Oregon) in 1946, and has been designated a National Historic Mechanical Engineering Landmark by ASME.[1] The technology became popular in Sweden in the 1970's, and has been growing slowly in worldwide acceptance since then. Open loop systems dominated the market until the development of polybutylene pipe in 1979 made closed loop systems economically viable.[1] As of 2004, there are over a million units installed worldwide providing 12 GW of thermal capacity.[2] Each year, about 80,000 units are installed in the USA and 27,000 in Sweden.[2]

This paper deals with utilization of energy storage systems. The shape of the daily consumption diagram, its weekly and seasonal diversification and their statistical features depend on the behaviour of the different consumer groups. In an electricity power system based on thermal, nuclear, hydro and renewable generation, the storage systems will find a wide field of application and may perform various duties, which must be taken into consideration in order to gain the largest possible advantage in optimization of the supply side.

This contribution deals with the problems of failure intensity of big power plant‘s blocks basely on bathtub curve of blackouts, command of operation and blackouts caused by wastage. The failure intensity is in most cases expresed by the Weibull two-parameters distribution.

This paper entitled “Voltage control and energy losses” deals with the problem of the losses in the transmission system in the case of voltage control by control of reactive power of a generator.

This work describes the procedure of modeling single parameters of general loads from which I chose induction motor and, of course, generator electrical energy – wind turbine. I used the program Matlab for the simulation of the connection between wind power plant and electrical network. I simulated startup of wind turbine and changes of wind flowing. I draw graphs of harmonic frequency of current and voltage based on these changes.

Distributed sources such as wind generators are becoming very imported part of power system in last few years. This paper deals about modeling possibilities of distributed sources connected to power systems using by MATLAB program. Simulations performed by MATLAB/Simulnik can have an important role in terms of evaluation of connecting conditions depended on small short-circuit power, which is usually in most places where distributed sources can be connected, very small. There will be five MATLAB/Simulink demo models introduced in this paper as examples of MATLAB/Simulink possibilities.

This paper entitled Energy building certification– input data deals with the new standard EN 15 193 and input data entering the assessment.

Approach to design of outer electric lines has changed in last years very significantly. Especially new demands in branch reliability should designer keep in mind. These new requests are basis of new European and national standards. To simplify design layout, automate verification of all rules and limitations and minimize mistakes computer application was developed to solve these tasks.

Submitted paper is aimed on questions of stand, safety and economics of wind energy.

The construction of power plant’s blocks with bigger output, better parameters and with higher level of automation lay higher requirements on reliability of power blocks. The results from operation show that with increasing size of blocks the reliability goes down. This decrease is manifested by higher number of blackouts. This contribution deals with problems of current state of reliability in operation.