A comparison of the NFRC and CEN thermal transmittance calculation methods in North America’s eight climate zones.

Studies have found that the CEN and NFRC methods produce different U-values for the same window. A comparative evaluation of the NFRC and CEN U-value calculation methods was conducted for North American residential high performance window products, as well as several parameters that are most influential in determining the whole window U-value for high performance windows, when utilizing different assumptions and boundary conditions, in North America’s eight climate zones. Using 2-D simulation software, THERM and WINDOW, four North American high performance frame types with double, triple and quad glazing combinations, were simulated and calculated according to the NFRC and CEN standard methods. Overall, the trend showed that for the specific window combinations of this study, the higher the performance of the IGU, the lesser the differences in the whole window U-value of both methods. Several strategies were proposed to support the possibility of the harmonization of both calculation methods.

A comparison of the NFRC and CEN thermal transmittance calculation methods in North America’s eight climate zones.

Studies have found that the CEN and NFRC methods produce different U-values for the same window. A comparative evaluation of the NFRC and CEN U-value calculation methods was conducted for North American residential high performance window products, as well as several parameters that are most influential in determining the whole window U-value for high performance windows, when utilizing different assumptions and boundary conditions, in North America’s eight climate zones. Using 2-D simulation software, THERM and WINDOW, four North American high performance frame types with double, triple and quad glazing combinations, were simulated and calculated according to the NFRC and CEN standard methods. Overall, the trend showed that for the specific window combinations of this study, the higher the performance of the IGU, the lesser the differences in the whole window U-value of both methods. Several strategies were proposed to support the possibility of the harmonization of both calculation methods.

Towards harmonizing the NFRC and CEN window performance simulation methods

Studies have found that the European Committee for Standardization (CEN) and National Fenestration Rating Council (NFRC) methods produce different U-values for the same window resulting in confusion when comparing products. A comparative evaluation of the NFRC and CEN U-value calculation methods was conducted for North American residential high-performance window products with focus on the most influential parameters in determining the whole window U-value for high-performance windows. Using two-dimensional conduction simulation software, four North American high-performance frame types with double, triple, and quad glazing combinations were simulated and calculated according to the NFRC and CEN standard methods. Overall, the trend showed that for the specific window combinations of this study, the higher the performance of the insulated glazing unit (IGU), the lesser the differences in the whole window U-value of both methods. The results showed an overall difference of 1 to 11% in whole window U-value when using the NFRC and CEN standards, lower than other studies. Generally, the NFRC standard resulted in the lower U-value for each case. Recommendations for harmonization of the two standards include aligning boundary conditions, frame cavity models, and material conductivities.

Brundibár – A Children’s Opera: History and Present

The paper focuses on the opera Brundibár. The authorial couple – composer Hans Krasa and librettist Adolf Hoffmeister – wrote it in the period of growing interest of artists in pedagogical aspects of the works of art. The changed social climate, however, meant for the work an unplanned journey – during the Second World War it was performed inside the Terezin ghetto by its inhabitants. The human message of the fairy tale story has thus been elevated into a higher symbolic frame – a resistance against the arrogance of power and violence. Especially the post-war era followed this symbolism. The author of the paper contemplates the innovative interpretative levels whose ambition is to cross the traditional performance frame of the work and to find connections with problems of contemporary society.

Comprehensive Review and Comparative Analysis of Hardware Architectures for Sobel Edge Detector

This paper presents a comprehensive review and a comparative study of various hardware/FPGA implementations of Sobel edge detector and explored different architectures for Sobel gradient computation unit in order to show the various trade-offs involved in choosing one over another. The different architectures using pipelining and/or parallelism (key methodologies for improving the performance/frame rates) are explored for gradient computation unit in Sobel edge detector. How the different architectures affected performance (in terms of video frame rate and image size) and area (in terms of FPGA resources usages) has been demonstrated. By exploiting the trade-offs between video frame rate, image size, and FPGA resources a designer should be able to find an optimal architecture for a given application.