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Recently, solar energy conversion has become a very actual item, especially when the world faces problems of petroleum supply and there has been a growing demand for using renewable energy sources. this situation an important question araises how to use solar energy optimally. The quantum efficiency solar cells depends on many factors: temperature, insolation, spectral characteristics of sunlight, etc. Some of these factors may be changed during exploitation of solar systems in order to increase their efficiency. The paper reports on the influence of temperature on the work efficiency of monocrystaline photovoltaic modules in hybrid solar systems in the conditions of south--eastern Poland. [ABSTRACT FROM AUTHOR]

This paper presents a concept of the air quality monitoring system design and describes a selection of data quality analysis methods. A high level of industrialisation affects the risk of natural disasters related to environmental pollution such as e.g. air pollution by gases and clouds of dust (carbon monoxide, sulphur oxides, nitrogen oxides). That is why researches related to the monitoring this type of phenomena are extremely important. Low-cost air quality sensors are more commonly used to monitor air parameters in urban areas. These types of sensors are used to obtain an image of the spatiotemporal variability in the concentration of air pollutants. Aside from their low price , which is important from a point of view of the economic accessibility of society, low-cost sensors are prone to produce erroneous results compared to professional air quality monitors. The described study focuses on the analysis of outliers as particularly interesting for further analysis, as well as modelling with machine learning methods for air quality assessment in the city of Lublin.

This article aims to show the possible energy savings in intelligent building installations due to the use of programmable mechanical multifunctional buttons. Two monostable buttons were placed, the pressing of which triggered the entire sequence of programmed actions and procedures. The consumption of electricity from the period before and after the assembly of the buttons was compared. The measured effects of using the buttons have shown that the energy consumption has decreased by approximately 7.5 kWh per month. The low installation costs and benefits resulting from the use of such a solution make it a cost-effective and a very convenient solution.

Abstract: Background: There are a number of reported cases of decompression sickness (DCS) with haemorrhages. These cases have not been sufficiently investigated and thus bleeding complications could not be directly correlated to the enhanced fibrinolysis. Objectives: The effect of hyperbaric exposition and decompression on the main components of fibrinolytic system has been measured. Methods: Two groups of 25 male divers each were subjected to hyperbaric exposures to the pressure of either 400 kPa – group I – or 700 kPa — group II followed by a staged decompression. The divers were monitored for clinical symptoms of DCS and checked for Doppler-detected venous gas bubbles. Venous blood was drawn from divers before exposition and 15 min after decompression. The concentrations and activities of t-PA and PAI-1 as well as concentrations of PAP and alpha2-antiplasmin and activity of factor XIIa were measured. Results: In all groups of divers no cases of DCS as well as detectable gas bubbles were noted. We observed elevated concentration of PAP, decreased concentration of alpha2-AP, decreased PAI-1 concentration and activity. There were no significant changes in factor XIIa activity as well as of t-PA concentration and activity. Conclusions: Hyperbaric exposition and decompression induce activation of fibrinolysis, even in the absence of detectable gas bubbles. Fibrinolytic activity increases mainly due to decrease of PAI-1 concentration and activity. Further clinical trials are necessary for the estimation of the importance of activation of fibrinolysis with decreased level of PAI-1 and alpha2-AP as a possible risk factor for bleeding in divers. [Copyright &y& Elsevier]