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The paper deals with performance analysis of potential application of glazed photovoltaic-thermal collector for domestic hot water preparation for multifamily building in European climatic conditions. Two different solutions are studied, glazed photovoltaic-thermal collectors integrated in the building envelope and glazed photovoltaic-thermal collectors fixed on the roof of the building. Moreover, the paper presents a comparison with conventional side by side installation of solar thermal collectors and photovoltaic panels to show the benefit of photovoltaic-thermal collectors. Simulation analysis has been done in TRNSYS with use of developed and validated mathematical model of glazed photovoltaic-thermal collector.

Testing of two facade modules under outdoor climatic conditions of Central Europe has been performed for more than two years. The paper analyses the results of long-term monitoring and shows potential benefits of prismatic glazing and photovoltaic-thermal (PVT) collectors integrated into one component. The prismatic glazing reflects beam radiation during summer period and transmits it during the winter period. During summer month solar irradiation transmitted through the prismatic glazing can be about 44 % lower compared to conventional triple glazing. Glazed PVT collector generates heat and electricity simultaneously. PVT collector integrated in the façade module can achieve solar yield during summer 58 kWh/m2.month in heat and 6,3 kWh/m2.month in electricity.

The simulation analysis of the solar hot water preparation system for an apartment building is presented. The analyses investigated the effect of climatic conditions on the efficiency of the solar system. To demonstrate the influence of climatic conditions, four building locations (Stockholm, Prague, Milan, and Barcelona), six different solar collectors, and six different design areas of solar collector field were used. The aim was to verify how the efficiency of the solar system varies depending on the climatic and design conditions. Moreover, the influence of year-to-year fluctuations of climatic conditions was also explored. The analysis has been provided by using TRNSYS simulation software over the period of one year using the time step of 2 minutes. The simulation results clearly showed that the efficiency of the SDHW system is dependent on the climatic conditions, especially on the air temperature. On the other hand, year-to-year weather fluctuations do not strongly affect the efficiency of the SDHW system.

The simulation analysis of the potential energy savings from the prismatic glass structure has been provided. The two conventional triple glazings and two proposed triple glazings with prismatic glass have been experimentally tested to obtain the realistic angular selective optical properties. The experimental results have been compared with conventional triple glazing with clear glass panes and triple glazing with solar control pane applied. The comparison indicated high potential advantages of triple glazing with prismatic glass structures (especially for reverse symmetrical prism): low transmittance for high solar altitude–summer condition, high transmittance for low solar altitude–winter condition. The obtained transmittance characteristics were used as input data for the annual simulation of a typical office in the Czech Republic. The simulation has been performed in TRNSYS and TRNBuild software. The gathered results confirmed, that prismatic glass structure can bring energy savings for both cooling and heating energy demands.

Introduction: Dysphagia after anterior cervical discectomy and fusion (ACDF) is a regular complication. The aim of this study was to identify risk factors for incidence and severity of dysphagia after ACDF with zero-profile spacer., Methods: Incidence and severity of dysphagia was evaluated preoperatively and for time of three years after ACDF (regular outpatient check-ups) ‒ prospective study with 3-years follow-up. Severity of dysphagia was assessed subjectively using Bazaz‒Yoo dysphagia score. Influence of selected factors on the incidence and severity of postoperative dysphagia was evaluated. Following statistical methods were used: Fisher's exact test, unpaired Student's t-test, one-way ANOVA and Spearman's correlation coefficient. Level of significance was defined as p ˂ 0.05. Correlations between paired parameters were evaluated according to Spearman's correlation., Results: Our study included 133 patients who underwent one-, two- or three-level ACDF with zero-profile spacer in years 2013‒2018. Myelopathy and GERD had significant impact on incidence and severity of pre-existing dysphagia. Risk factors for incidence of dysphagia after ACDF were number of treated segments, myelopathy, pre-existing dysphagia and surgery of C4/5 segment. Age of patients, duration of surgery and pre-existing dysphagia correlated positively very weakly to weakly with severity of dysphagia after ACDF. Number of treated segments, myelopathy, GERD and surgery of the C4/5 segment were risk factors for greater severity of postoperative dysphagia., Conclusion: Risk factors for incidence and severity of pre-existing dysphagia were myelopathy and GERD. Risk factors for dysphagia incidence after ACDF were number of treated segments, pre-existing dysphagia, myelopathy and surgery of C4/5 segment (Tab. 6, Fig. 1, Ref. 30).