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Abstract

Air Pollution in Poland – Condition, Causes and Effects. In the recent years the air in Poland seems to be the most polluted in Europe (it is worse only in a few times smaller Bulgaria). The concentration of particulate matter PM10 and PM2.5 and polycyclic aromatic hydrocarbons (PAHs), represented by benzo(a)pyrene are among the highest in European Union countries. They are highly toxic, especially PAHS, which damage the hematopoietic system, accumulate in living organisms leading to a cancerous process, they cause damages to the central nervous system and infertility. It is estimated that high air pollution causes 45-47 thousands premature deaths in Poland every year, as well as growth frequency of allergies and chronic diseases. Polish society loses about 520,000 potential years of life, and the economy of 18.5 million work days. It’s a very high price. The weather determines to a large extent the air pollution. The smog episode is usually accompanied by low wind speed or atmospheric silence, reduction of visibility and thermal inversions. However, the biggest problem is low emission, which is mainly related to individual heating of buildings (78-87% of the total emission of benzo(a)pyrene. The reasons for such poor sanitary condition of the air in Poland are complex and to a large extent they result from spatial chaos and lack of spatial planning, but also from general policy country. The most important reasons are i.a.: the lack of a planning policy and a sustainable transport policy, persistent subsidies for unprofitable coal mines, the lack of a policy promoting renewable energy sources and “clean” technologies, high gas price (the highest in Europe) and no subsidies for the poorest, scattered buildings which hinders access to system heat, inefficient and unsuitable transport based on road transport road and individual cars (often old, Diesel) etc.
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Abstract

This article presents the main stages and challenges in modelling and designing of modern ultrasonic welding and cutting systems. First, the key components of such a system, such as an ultrasonic stack (con- sisting of a high power ultrasonic transducer and a sonotrode) and a digitally controlled ultrasonic power supply with precise control of the output power, have been considered. Next, a concept of measurement system for verification and validation of mathematical models of ultrasonic stacks and its components has been presented. Finally, a method of ultrasonic stack e-diagnosis based on ultrasonic transducer electrical impedance measurement during welding and cutting process has been described
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