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Periodicity of temperature on three stations in the Nisava River valley in period 1949-2014, has been analyzed by means of Fourier and wavelet transforms. Combined periodogram based on fast Fourier transform shows considerable similarity among individual series and identifies significant periods on 2.2, 2.7, 3.3, 5, 6-7, and 8.2 years in all datasets. Wavelet coherence analysis connects strongest 6-7 years spectral component to Mediterranean oscillation, starting in 1980s. Combined periodogram of Mediterranean oscillation index reveals 6-7 years spectral component as a dominant mode in period 1949-2014. Wavelet power spectra and partial combined periodograms show absence of 6-7 years component before 1975, after which this component becomes dominant in the spectrum. Consistency between alternation in temperature trend in the Nisava River valley and change in periodicity of Mediterranean oscillation was found. [ABSTRACT FROM AUTHOR]

The changes and oscillations in air temperature during the second half of the 20th and in the early 21st century, have become one of the major concerns of almost all scientific disciplines. Such changes are noticeable both at the local and global level. The objective of this paper is to point out that the changes of this climate element can also be detected at the local level. The research underlying this paper is, in terms of territory, limited to the Sokobanja basin in Eastern Serbia. The analysis relies on the data on air temperature for the period 1946-2012 taken from the Meteorological weather station located in Sokobanja. The obtained data were processed in line with the recommendations of the World Meteorological Organization. The evidenced statistically significant changes in air temperature were examined using the following statistical tests: Pettit test, Standard Normal Homogeneity test, Buishand range test, and von Neumann test. [ABSTRACT FROM AUTHOR]

The paper introduces basic information on the geographical location, climate and solar radiation in Serbia. It focuses particularly on the air pollution in Serbia and its influence on the solar cells energy efficiency. Moreover, detailed information on the development of solar energy in Serbia and the examples of the application of the low, medium and high temperature and photovoltaic conversion of solar radiation is provided. The paper also gives an overview of the installed greater capacity solar power stations related to the electricity network and the smaller capacity solar power stations as the independent sources of electricity in Serbia. In conclusion, the paper stresses Serbia's favourite climate and other conditions for the prospective successful development of solar energy. [ABSTRACT FROM AUTHOR]

In mid-July 2012, hundreds of fires spread over forest stands in the south of Europe. Considering available satellite and meteorological data we have tried to determine a method using analogy, whether these fires were preceded by the intensified solar activity. The justification of this approach lies in the belief that it is impossible by direct or indirect activity of man to set fire at the same time to the sites that are geographically separated. In this paper we have tried to test the hypothesis claiming that charged particles coming to us from the Sun may be responsible for the number of forest fires. Unlike some other situations when the potential explanation could be a sudden influx of the protons of different energy ranges, in our study, there are electrons as carriers of the potential explanation. Many previous studies results have shown that there is statistically significant relationship between the processes on the Sun and certain movements of air masses in the atmosphere our planet. The presented results in this paper of the correlation relationships between the mean hourly flows of electrons and the mean hourly air temperatures in Belgrade and Rome and the analysis of the synoptic situation as a function of the suggested model so far, indicate that the number of fires that were occurring more than a week, from July 15, 2012, in the south of Europe, were caused by electrons coming from the Sun. [ABSTRACT FROM AUTHOR]

This paper gives the results of the electricity generated by the fixed, one-axis and dual-axis tracking photovoltaic solar plant of 1 MW with flat panels made of monocrystalline silicon which is to be built in the area of Sokobanja (spa in Serbia). Further on follows a description of the functioning of the fixed and one-axis and dual-axis tracking solar plants. For the calculation of the electricity generated by these plants PVGIS program was used. Calculations have shown that fixed photovoltaic solar plant power of 1 MW, solar modules of mono-crystalline silicon yield 1130000 kWh power output, one-axis tracking solar plant yields 1420000 kWh, and dual-axis tracking solar plant yields 1450000 kWh of electricity. Electricity generated by the fixed photovoltaic solar plant could satisfy 86% of the annual needs for the electricity of the „Zdravljak“ hotel and the special "Novi stacionar" hospital in Sokobanja. [ABSTRACT FROM AUTHOR]