THE CONTRIBUTION OF HEAT PUMPS TO REDUCTION OF CARBON DIOXIDE GENERATION DURING THE PROCESS OF COMBUSTION

The aim of the paper is to propose a method of heating and hot water preparation using a heat pump based on the analysis of the heat losses calculated for the purposes of an office building, which is a part of a medium-sized production plant. In this respect, the original gas boilers will be replaced with alternative energy devices, which will lead to heat and power savings and reduction of carbon dioxide emissions released into the atmosphere

Internet Connection variants using present TV cable wiring

Práce pojednává o datových přenosech po stávajících rozvodech kabelové televize. K realizaci daného projektu byla vybrána zařízení PLC. Rozebíraná je problematika vícetónových modulací a blíže byla popsaná modulace OFDM, kterou daná zařízení využívají. Dále byl popsán postup integrace zařízení PLC na kabelovou síť, úpravy kabelové sítě a základní topologie vytvořených datových síti. Bylo nahlédnuto na PLC modem a Head End od firmy Corinex, které byli použity při realizaci datové sítě ve vybrané obci. Také jsem zde uvedl úskalí kabelových vedení při tomto druhu datových přenosů a řešení některých vzniklých problémů. V reálným provozu byly potom testované parametry vytvořené sítě. Byly změřeny přenosové rychlosti na fyzické a transportní vrstvě a dále pak SNR jednotlivých spojení a útlum signálu. Měření potvrdily vhodnost použití PLC zařízení na přenos dat po kabelových sítích - co se týče přenosové rychlosti, ale také dosahu. Jako příloha je uvedená mapa kabelové televize s vyznačením umístnění PLC zařízení ve vybrané kabelové síti.This dissertation examines data transfers along the existing lines of cable TV. PLC equipment has been selected as the focus of this examination. The essay examines the question of Multicarrier modulation and focuses more specifically onto the problem of OFDM modulation, which is being used by the selected equipment. It further describes the process of integration of PLC equipment into the cable TV network, modifications of the CATV and the basic topology of the created data networks. The essay also offers a closer look onto a PLC modem and Head End from Corinex that have been used in the implementation of a data network in a selected rural settlement. The author has also raised the issue of the problems connected with cable wires connected with this particular type of data transfers and the solutions of some of the encountered problems. The characteristics of this network have then been measured during normal operation of the created network. Measurements have been carried out in order to determine the transfer speed on a physical and transfer level, the SNR of specific connections and the signal attenuation. The measurements have confirmed the suitability of the used PLC equipment for the purposes of data transfer along the cable TV lines as far as data speed and signal strength was concerned. A map of the particular cable TV lines and the PLC equipment has been included in the attachment.

Niekonwencjonalne podejście pedagogiczne i edukacyjne w wybranych szkołach alternatywnych w okresie istnienia Czechosłowacji (1918-1939)

The reform pedagogical movement in the period of the Czechoslovak Republic (CSR) helped educators to change standard pedagogical and educational approaches, which were typical of the Herbarttype schools. The paper concentrates on the analysis of pedagogical activities of chosen members of this movement in the first decade of the new state. They were inspired by the ideas of important world personalities such as J. Dewey, M. Montessori, E. Key, H. Parkhurst, etc., and were active in individual alternative classes, resp. schools, but their activity was limited to them only as they did not find any continuators of their effort in the period under consideration.3951153028Studia Edukacyjn

Implementation of Simple WPNC System on the Experimental Transceiver Network Testbed

V této práci vyvíjíme simulaci bezdrátové sítě, konkrétně sítě využívající principy WPNC. Na začátku jsou odvozeny estimátory pro H-MAC a H-BC kanály. Následuje implementace odvozených estimátorů v MATLABu společně s implementací pomocných objektů a funkcí. Dále prezentujeme softwarová rádia a jejich vlastnosti. Základní, čistě počítačová simulace přenosu one-to-one je vytvořená v MATLABu, za ní následuje simulace využívající softwarová rádia. Na konci jsou prezentovány přijaté obrázky. Z matematických metod byla použita Monte Carlo Integrace a odvození s pomocí skalárního součinu. Z programovacích technik bylo použito Objektově orientované a funcionální programování s aplikací vektorových operací. Jedním z nejvýznamnějších výsledků této práce je úspěšný přenos a dekódování několika Hierarchických rámců v H-MAC kanálu v simulaci se softwarovými rádii.In the thesis we develop a simulation of a wireless network. Specifically, a network that uses WPNC principles. In the beginning, there are estimators for H-MAC and H-BC derived. A MATLAB implementation of the estimators follows together with implementation of auxiliary objects and functions. Next, software radios are presented and their properties are examined. A basic MATLAB pure-computer simulation of a one-to-one transmission is developed followed by over-the-air simulation. In the end, resulted received pictures are examined. From the math methods, Monte Carlo Integration and derivations with dot product were used. From the programming methods, Object Oriented and Functional Programming were used with vectorized operations. One of the significant results of the work is a successful transmission, reception and decoding of several Hierarchical frames in H-MAC stage in the over-the-air simulation

Thermal and performance analysis of a gasification boiler and its energy efficiency optimization

The purpose of this study was to determine a method for multi-parametric output regulation of a gasification boiler especially designed for heating or for hot water heating in buildings. A new method of regulation is offered, namely more parametric regulation via proportional-integral-derivative (PID) controllers that are capable of controlling the calculated values of pressure, temperature and fan speed. These values of pressure, temperature and fan speed are calculated in a completely new way, and calculations of setpoints for determination of optimal parameters lead to an increase in boilers efficiency and power output. Results of measurements show that changes at the mouth of the stack draft due atmospheric influences occur in times with high intensity and high frequency, while power parameters, or boiler power output amplitudes and fan speed automatically "copy" those changes proportionally due to instantaneous fan speed changes. The proposed method of regulation of the gasification boiler power output according to the technical solution enables a simple, cheap, express and continuous maintenance of high power output at low concentrations of the exhaust gases of the gasification boilers from the viewpoint of the boiler user, as well as from the perspective of development and production it allows a continuous control monitoring of these parameters.Web of Science107art. no. 106

POSSIBILITIES OF HEAT LOSS REDUCTION DURING HOT WATER PREPARATION IN RESIDENTIAL BUILDINGS

The aim of the article is based on an analysis of heat losses arisen before the renovation of hot water distribution pipeline of a selected residential building and after the subsequent renovation is to design possibilities for more efficient insulation. Three alternatives of insulation thickness in terms of heat loss along with the condition of the existing isolation after the renovation of the distribution pipelines and with the condition before the renovation are compared in the article. By choosing a suitable insulation, energy efficiently operation will take place in the hot water supply which has a direct impact on operation economy, and finally it leads to reduction of environment pollution through fossil fuels saving

THE IMPACT OF THE COMPOSITION OF THE WOOD GAS TO EMISSIONS AFTER COMBUSTION OF WOOD GAS

This paper presents the results of measurements which were carried out on Department of furnaces and thermal technology. Experiments were carried out on a countercurrent gasifier using different fuels, different flow gasification medium and different heights of backfill. In order to obtain values for emissions of the combustion process of producer gas are planned measurements for different composition of produced gas, depending on the type of gasifying medium. In our case, produced gas will be incinerated in the boiler or the cogeneration unit. These measurements are planned for in autumn 2014. The obtained data can serve as a basis for the use of produced gas in industrial practice

Microstructure and mechanical properties of sintered and heat-treated HfNbTaTiZr high entropy alloy

High entropy alloys (HEAs) have attracted researchers' interest in recent years. The aim of this work was to prepare the HfNbTaTiZr high entropy alloy via the powder metallurgy process and characterize its properties. The powder metallurgy process is a prospective solution for the synthesis of various alloys and has several advantages over arc melting (e.g., no dendritic structure, near net-shape, etc.). Cold isostatic pressing of blended elemental powders and subsequent sintering at 1400 degrees C for various time periods up to 64 h was used. Certain residual porosity, as well as bcc2 (Nb- and Ta-rich) and hcp (Zr- and Hf-rich) phases, remained in the bcc microstructure after sintering. The bcc2 phase was completely eliminated during annealing (1200 degrees C/1h) and subsequent water quenching. The hardness values of the sintered specimens ranged from 300 to 400 HV10. The grain coarsening during sintering was significantly limited and the maximum average grain diameter after 64 h of sintering was approximately 60 mu m. The compression strength at 800 degrees C was 370 MPa and decreased to 47 MPa at 1200 degrees C. Porosity can be removed during the hot deformation process, leading to an increase in hardness to similar to 450 HV10.Web of Science912art. no. 132

POSSIBILITIES OF HEAT LOSS REDUCTION DURING HOT WATER PREPARATION IN RESIDENTIAL BUILDINGS

The aim of the article is based on an analysis of heat losses arisen before the renovation of hot water distribution pipeline of a selected residential building and after the subsequent renovation is to design possibilities for more efficient insulation. Three alternatives of insulation thickness in terms of heat loss along with the condition of the existing isolation after the renovation of the distribution pipelines and with the condition before the renovation are compared in the article. By choosing a suitable insulation, energy efficiently operation will take place in the hot water supply which has a direct impact on operation economy, and finally it leads to reduction of environment pollution through fossil fuels saving