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Preparation and characterization of a selective polymer-based solar absorber for building integration
(MDPI, 2020-11-06) Čekon, Miroslav; Struhala, Karel; Kopkáně, Daniel
Recent technological advances in solar absorber production may have opened ways for new applications of these materials in buildings. A low-emissivity enhanced polymer-based absorber foil was developed and prototyped using mass-production industrial roll-to-roll process to demonstrate feasibility of the concept. This paper describes key development factors leading to particular composition of the prototype and its testing, especially spectroscopy measurements (both for shortwave and longwave regions) and environmental impact assessment. It also provides comparison of tested parameters with commercially available products. The results show that the developed absorber has fairly good thermal emissivity (around of 0.3), high solar absorption level (0.95) and significantly lower (up to 98 %) environmental impacts compared to the commercially available metal-based solar selective absorbers.
Unemployment Effects of Greenfield and Brownfield Investments in Post-transition European Union Members
(Technická univerzita v Liberci, 2020-10-08) Bayar, Yilmaz; Remeikiene, Rita; Žufan, Jan; Novotný, Miloslav
International direct and portfolio investments have gone up considerably as of mid-1980s. The foreign direct investments with characteristic of long term horizon may affect the economic variables through know-how and technology transfer, physical capital expansion, and new job creation. However, foreign direct investments may have potential to negatively affect the domestic competitors with insufficient competitiveness in the industry. So, the economic effects of FDI inflows have been one of the much-debated and studied issues in the international economics. This study investigates the unemployment effects of greenfield and brownfield investments in 11 post-transition EU members over 2003-2017 period through panel cointegration and causality tests. The article fills the gap in the literature, because the relevant empirical literature has generally researched the impact of total FDI flows on the unemployment/employment. The empirical findings revealed that brownfield investments raised the unemployment in overall panel in the long run, but greenfield investments had no significant impacts on the unemployment in overall panel in the long run. However, greenfield investments decreased the unemployment in Croatia, Hungary, and Slovenia, and raised the unemployment in Poland and Slovakia, while brownfield investments raised the unemployment only in Czechia. Consequently, it is not very reasonable to compare our findings with the results of other studies using total FDI inflows as the independent variable. But, it is generally consistent with theoretical and empirical expectations.
Evaluation of the Fiscal Decentralization: Case Studies of European Union
(KAUNAS UNIV TECHNOL, 2020-10-02) Slavinskaite, Neringa; Novotný, Miloslav; Gedvilaite, Dainora
Fiscal decentralization has been widely discussed at various levels and from various perspectives. The Organization for Economic Co-operation and Development (the OECD), similar to the World Bank, also pays great attention to it. Fiscal decentralization has always been an interesting investigation topic, and the researchers, in addition to considering the future of the economy, study this problem from different perspectives, i.e. geographic, political and others. The effect of fiscal decentralization on the economic development of the state has been investigated by various authors. Three different hypotheses provide the proofs of the positive effect of fiscal decentralization. The main advantage of fiscal federalism are efficient and adequate public services which are provided locally through the mobility of the citizens, voting power and competition between the local governments in the created ecosystem. The potential advantages of the competition among the local government powers are similar to the advantages associated with the competition on the private markets. The paper is focussed on fiscal decentralization of the state. It aims to investigate the theoretical aspect of the impact of fiscal decentralization on the economic development to calculate the index of fiscal decentralization and to evaluate the effect of fiscal decentralization on the economic development in the particular states of the European Union. Thus, Bulgaria and Lithuania have the lowest fiscal decentralization index of EU-13 (0.28), while the Czech Republic has the highest index (0.46). The researchers have proved the effect of fiscal decentralization on the economic development of the EU-13 states to be statistically significant and positive. The originality of this paper is that it introduces a theoretical model for evaluating the fiscal decentralization effect on the economic development and assesses the fiscal decentralization effect on the economic development of the particular EU-13 states.
Evaluation of microwave drying effects on historical brickwork and modern building materials
(IOP Publishing, 2020-10-15) Kvapilová, Vendula
One of the most common reasons for any construction work requirements is an increased humidity of the building. Increased humidity does not affect only buildings with basement, but also buildings without it, which were not properly hydro-isolated or the hydro isolation was damaged due to aging or to adverse environmental effects. Such situations are solved with designing suitable remediation measures, which necessarily includes drying of damp masonry as well. This almost always includes historical buildings, where protection against groundwater was never planned. Such buildings are usually very sensitive to any physical intervention into construction itself and destructive methods of revitalization are very often completely out of the question, therefore it is necessary to develop methods, which can be used particularly for historical buildings. This article focuses on evaluating effects of microwave drying historical brickwork as well as modern building materials. First, the method of microwave drying is described in general, then we cover the experiment, which was performed at the Faculty of Civil Engineering at Brno University of Technology. The experiment was applied on two pillars made of historical brickwork. Those samples were being thoroughly analysed during the drying process and final outcomes were compared to already existing experiments on modern materials. The goal of this work is to find out, if the method of microwave drying is more suitable for described conditions and also to set such process of drying, which would provide the highest effectivity.
Use of EMW radiation in the building industry at defects in buildings
(MATEC Web of Conferences, 8th International Scientific Conference Building Defects (Building Defects 2016), 2016-12-22) Sobotka, Jindřich; Smolka, Radim
This paper discusses theory and application of microwave radiation and experimental optimization of microwave radiation to eliminate moisture content in wood elements. It will be appreciated that the rising moisture leaking into the structure, resulting in defects and structures of the buildings themselves. Owing to its properties, microwave radiation has been used in the construction industry in modern times, in particular to dry wet masonry of buildings. Effects of electromagnetic radiation on building structures lead to relatively sharp decreases in moisture content from damp building structures or elements. The influence of electromagnetic radiation on building structures lead to oscillation of water molecules contained in the material, which cause a phase transformation of water into vapour. Consequently, the vapour evaporates from the moist material, thereby drying the element exposed to radiation. The article describes experiments carried out at the Faculty of Civil Engineering of the Faculty of Technology in Brno that demonstrate successful decrease of water content in building materials using microwave radiation. First, the understanding of microwave radiation will be discussed. Following an analysis of research results an optimum intensity of microwave radiation sources as well as the necessary length of the irradiation of microwave radiation have been determined with respect to the particular type of building material and the success rate of elimination of moisture.

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