On the Bergman representative coordinates

We study the set where the so-called Bergman representative coordinates (or Bergman functions) form an immersion. We provide an estimate of the size of a maximal geodesic ball with respect to the Bergman metric, contained in this set. By concrete examples we show that these estimates are the best possible.Comment: 20 page

A remark on the dimension of the Bergman space of some Hartogs domains

Let D be a Hartogs domain of the form D={(z,w) \in CxC^N : |w| < e^{-u(z)}} where u is a subharmonic function on C. We prove that the Bergman space of holomorphic and square integrable functions on D is either trivial or infinite dimensional.Comment: 12 page

Analysis of the Microbial Efficiency of the Nanosilver Filter Materials

Indoor air quality is an important factor influencing the human health and well-being. It is just as important as the quality of the outdoor air, as people spend most of their lives staying indoors. In order to improve the quality, it is vital to use the right filters that clean the air of chemical, physical and biological pollutants. Filtration efficiency largely depends on the filter material. Currently, polyester fibers, glass, polyurethane and latex are used for the production of filter fabrics. One of the latest solutions are filter materials coated with nanosilver disinfectant. Tests have been carried out in order to determine the microbiological efficiency of the nanosilver filter material (class F5, F7, F9) for the presence of the three most common strains of bacteria in the indoor air (Micrococcus luteus, Bacillus subtilis, Pseudomonas fluorescens). On the basis of results read 24, 72 hours and 7, 14 and 30 days after the drying-out of filters, the effect of the filter material treated with nanosilver on the growth of bacterial cells was established. The results allowed to determine the effectiveness of filters with nanosilver. They inhibit the growth of bacteria, both gram positive and gram negative. They also provide better indoor air quality, restrict the amount of biological pollution by reducing the growth of microorganisms on the surface of the filters. Therefore, the filters with nanosilver have higher filtration efficiency. Moreover, they remain clean for a longer time compared to the air filters that are not covered by the antibacterial compound

Influence of modernization activities on demand of thermal energy in buildings

Państwa Unii Europejskiej, w tym Polska, stosując się do protokołu z Kioto, wprowadzają ograniczenia zużycia energii, a także starają się zwiększać udział energii pozyskiwanej ze źródeł odnawialnych. Obecnie energia odnawialna zaspokaja 15‚20% światowego zapotrzebowania na energię. Duży udział w globalnym zużyciu energii odnawialnej stanowi biomasa. Inne odnawialne źródła energii stanowią obecnie około 2%. Przewiduje się jednak, że w drugiej połowie XXI wieku ich udział może stanowić już od 20 do 50%. Rozwój technologii do pozyskiwania energii odnawialnych będzie się rozwijał, ponieważ koszty ich budowy w ciągu ostatnich 30 lat znacznie się obniżyły i nadal będą spadać, podczas gdy ceny ropy naftowej i gazu ziemnego ciągle będą wzrastać. Istotnym elementem ograniczania zużycia energii są oszczędności w sektorze budowlanym, gdzie obecnie zużywa się około 40% całkowitego końcowego zapotrzebowania na energię w Unii Europejskiej [1]. Elementem polityki UE w ograniczaniu eksploatacyjnej energochłonności budynków jest Dyrektywa 2002/91/EC, której celem jest poprawa charakterystyki energetycznej budynków już istniejących, jak i nowo projektowanych, z uwzględnieniem lokalnych klimatycznych warunków zewnętrznych, klimatu wewnętrznego i efektywności ekonomicznej. Dyrektywa wprowadza między innymi obowiązek sporządzania świadectw charakterystyki energetycznej dla budynków. W świadectwie przedstawia się ilość energii oszacowanej do pokrycia różnych potrzeb związanych ze standardowym użytkowaniem budynku (ogrzewanie, przygoto-wanie ciepłej wody, chłodzenie, wentylacja i oświetlenie, w przypadku budynków użyteczności publicznej). Zapotrzebowanie na energię wyraża się za pomocą wskaźników liczbowych (EP - wskaźnika energii pierwotnej, EK - wskaźnika energii końcowej), do których obliczenia niezbędne są dane dotyczące izolacyjności przegród budowlanych, instalacji, jak również lokalizacji, czyli usytuowania budynku względem stron świata. Wyliczone zapotrzebowanie na energię EP porównuje się z założeniami referencyjnymi.European Union Member States, including Poland, undertaken efforts to fulfill Kyoto Protocol limitation and energy consumption and increased participation of renewable energy resources in the overall production. Building construction and exploitation is among the most energy consuming activities. Absorption of energy in buildings is limited by Directive 2002/91/EC, which regulates either existing buildings and directions of their improvement or new buildings to be designed. In Poland guidelines from directive have been defined by package of legal acts, which includes the Ordinance of the Ministry of Infrastructure, issued January 21, 2008 regarding methodology of calculate characteristic of energy in buildings. This ordinance suggest, that index of primary energy EP compared with reference index evaluate power consumption in buildings. Existing building (heated area Af = 136.56 m2 and volume V = 520 m3) without basement, was considered for modernization decreasing energy consumption. As the starting point for the calculation was the coal-fired furnace controlled manually. Three different insulation materials groups, distinct type of additional installations (i.e: solar and ventilation system with heat recovery coefficient 0.8 as well as three different energy sources and their combination were con-sidered in simulations. The impact of modernization activities on the primary energy index (EP), final energy index (EK) and estimated annual cost of total consumption of energy building was considered. Based on simulations obtained that the change in isolation class building with isolation 1 to 2 causes an average rate of EP reduction for coal-fired furnace, gas furnace and condensing boiler of 20.5% and the biomass boiler by 11.1%. Changing the thickness of the isolation of the option 2 for Isolation 3 will be reducing respectively the rate of EP by 14.3% and 6.8%. The final energy demand of buildings was used to calculated estimated annual cost because only EK index take into account the size of usable energy. For example, in the case of the coal-fired furnace with the ventilation system and isolation 3 EP was 212.74 kWh / (m2.year) with an annual estimated cost of energy consumption 2298 zł/year. For comparison, the installation equipped with a biomass boiler and isolation 1 EP was 114.34 kWh /(m2.year) but the estimated annual cost of energy consumption was 5118 zł/year. Summarizing, only combination of biomass as a fuel and energy saving via proper insulation allows to achieve the reference index. Moreover reduction of EP index is not proper indicator of low annual cost of energy building consumption