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- ItemSunlight exposure conditions for buildings in European localities(Elsevier, 2024-12-02) Vychytil, Jaroslav; Mohelníková, JitkaSunlight exposure represents one of key parameters of indoor climate comfort, especially for residential buildings, schools and care homes. It depends on the sunlight time in specific design situations like a locality, building type, window size, position and orientation. A practical evaluation of sunlight access into buildings is based on a standard methodology in EN 17037. The methodology based on parameters of minimum solar altitude is specified for given geographical locality and time of the sunlight exposure evaluation. The aim of this study is to compare how the sunlight exposure is changed in European regions. The evaluation is based on the standard limitations to specify potentials for the building insolation assessments in different geographical localities. Research value of the study deals with the general overview of the sunlight potential of building insolation in different European climatic regions. It can be important for building design and urban planning process in those localities. The research is focused on determining the minimum solar altitude for 33 capitals and for all days from 1st February to 21st March specified by the standard to ensure the required minimum insolation time.
- ItemEXPLORING THE APPROACHES TOWARDS SUPPORT OF ACADEMIC ENTREPRENEURSHIP: EVIDENCE FROM AN EMERGING MARKET(VILNIUS GEDIMINAS TECH UNIV, 2024-12-24) Zinecker, Marek; Pěnčík, Jan; Kocmanová, Alena; Meluzín, Tomáš; Balcerzak, Adam Przemyslaw; Pietrzak, Michał BernardOver the past three decades, an exponentially growing body on elements and actors of the concept of an entrepreneurial university has emerged. Compared to its western European counterparts, however, the idea of the third role of the university has only recently been implemented in Central and Eastern European countries, and thus both research and entrepreneurial practice grapple with empirical results. In this paper, we attempt to fill this gap while adopting a case study approach to examine the issue of what resources a prominent technical university operating in the emerging market of the Czech Republic transfers to academic ventures to utilise and commercialise university research results. Within a survey, nine academic founders and two university representatives were interviewed to assess the role of university resources in facilitating academic entrepreneurship. Our research results suggest that creating infrastructure to foster the third role of universities in an emerging market is a complex and long-term issue. Formal institutions embedded in the intra-university organisational structure, such as knowledge transfer offices and entrepreneurial centres, need to be equipped with sufficient resources and competences. Skilled people with their own network of contacts to intra-university departments and external environment represented by regional incubators, venture capital providers, business angel associations, and experienced entrepreneurs should be involved in the process of creating and increasing capacity. Furthermore, the upcoming agenda should undoubtedly acknowledge the significant role of entrepreneurship education with a focus on talent recognition and entrepreneurship training to impact the entrepreneurial intentions of researchers and students. Overall, we also conclude that the motivation of academics to commercialise their inventions could be positively affected by the applied concepts of assessing their performance. Finally, this study shows that measures at all management levels have to be adopted to create a vital organisational culture that will be in alignment with the vision of entrepreneurial university. The novelty of this paper is twofold. First, the study provides a useful methodological concept of data collection as the multi-level approach was applied for studying the phenomenon of entrepreneurial university. Furthermore, the research findings have valuable implications for university authorities, as well as national and local policy makers, in creating growth programmes and supporting the entrepreneurial mindset.
- ItemSpatiotemporal Moisture Field(MDPI, 2024-11-02) Fuciman, Ondřej; Matějka, LiborFor monitoring capillary moisture conduction, the most important parameter is the moisture conductivity coefficient, which is a material characteristic; however, its use in practical calculations is not very common. For further development in the field of liquid moisture propagation, an automated measuring apparatus has been developed and granted a European patent. Its essence lies in detecting the liquid water content based on a well-known physical phenomenon: electromagnetic radiation in the microwave range. The determination of the spatiotemporal moisture field is the first and fundamental step for describing transportation phenomena. The moisture field thus created allows for the viewing of the moisture conductivity coefficient, which is one of the most important parameters in describing transportation phenomena as a function of moisture. The presence of water in building materials can significantly affect their physical properties, such as mechanical or thermal–technical characteristics. This may lead to unacceptable consequences, which might only manifest after a certain period of time. In the case of multi-layered structures, moisture can transfer from one material to another. Therefore, it is essential to address this process. The advantage of the software solution described by the methodology is the use of an open communication protocol in the form of a synchronized array, which is not common in typical applications of this type. The principle of separating hardware modules is also unusual for devices of this type, as it requires the independent communication of each module with the control software. Mutual communication is handled exclusively at the software level, making it possible to modify, optimize, or parameterize the procedures as needed. Upon closer examination of the wetting curves of various materials, anomalies were revealed in some of their structures. This can be advantageously utilized in the research of newly developed composite materials. The assembled system of measuring instruments, their software integration, and control provide a foundation for the practical application of the described procedures and methods for determining the moisture field of building materials. The parameterization of individual processes, as well as the open access to data, allows for the optimization of the methodology, as materials of entirely different characteristics may require an individual approach, which will certainly contribute to the advancement of science and research in this area. Currently, this work is being followed by further extensive studies, not yet published by the authors, focusing on the application of the described moisture field to evaluate the moisture conductivity coefficient as a function dependent on the material’s mass moisture content. Their application requires specific mathematical and programming approaches due to the significant volume of data involved.
- ItemEffect of Microwave Radiation on the Properties of Hydrogel, Cork, Perlite, and Ceramsite(MDPI, 2024-08-22) Průša, David; Šťastník, Stanislav; Svobodová, Kateřina; Šuhajda, Karel; Sochorová, ZuzanaThe present work analyzes the effect of releasing physically bound water from hydrogel, cork, perlite, and ceramsite on materials exposed to microwave radiation and subsequently investigates possible changes in the physical properties of these materials (water absorption and thermal conductivity coefficient). The release of physically bound water from individual materials has potential practical applications in materials engineering, for example, in the internal curing of concrete, where individual aggregates could, under the influence of microwave radiation, release water into the structure of the concrete and thus further cure it. Experimental analysis was carried out with samples of the above-mentioned materials, which were first weighed and then immersed in water for 24 h. Then, they were weighed again and exposed to microwave radiation. After exposure, the samples were weighed again, left immersed in water for 24 h, and weighed again. The focus of the study was on the ability of the aggregates to release water due to microwave radiation and on the changes in the properties (water absorption, thermal conductivity coefficient) of these materials when exposed to microwave radiation. The samples were further monitored by digital microscopy for possible changes in the surface layer of the materials. The hydrogels show the highest water absorption (1000%) and the fastest water release (45 min to complete desiccation). After the release of water due to microwave radiation, their ability to absorb water is maintained. Of interest, however, is that in the case of almost complete removal of water from the soaked hydrogel, the original powdered state of the hydrogel is not obtained, but the outcome has rather a solid structure. In the case of cork, the water absorption depends on the fraction of the material.
- ItemIncrease the internal surface temperature to eliminate surface condensation on the window(EDP Sciences, 2024-07-16) Vorlíčková, Petra; Kalousek, Miloš; Šoulová, EvaOne of the most critical places in buildings in terms of physical thermal properties are windows. This is the most frequent place where the temperature drops below the dew point and surface condensation, or mould, develops. The work deals with the study of the surface temperature courses at the critical points of window glazing and connection joints and the subsequent improvement of the initial unsatisfactory condition by using a patented technology, a conductive material without further intervention in the structure. In the case of a very unsatisfactory condition, a heating resistance wire was attached to the bar, which in combination with the bar distributes the heat to a wider area. The evaluation of the surface temperature increase was performed in a steady-state thermal analysis with fixed boundary conditions and then with the influence of the flow in a room with the heater placed under the window.