Acta Facultatis Ecologiae - Technická univerzita vo Zvolene

41180160140this reason we also picked of this function for thecharacterization of EMH. Our choice has also beeninfluenced by the work [9]. By means of nonlinearregression the coefficients A, B, j, C and y wereobtained to fit daily average waves for each monthwithin year 2004. The package Microcal ORIGIN6.0 was used for this purpose. Results are depictedin figures 4–8 and they lead to interesting conclusions.The annual mean value of EMH h remainsapproximately constant during the whole year ata level of 123.4 m. However, a potential by smallvariation cannot be rejected due to weak statistics.Deviations from the mean value are at a level of26 %. The coefficient B, representing a 24 h oscillationamplitude, varies inversely to the coefficientA. It reaches the minimum in September and themaximum at the beginning of January. The variationof the coefficient B deviates from its meanvalue at the level of 86 % and significantly anticorrelateswith 222 Rn activity concentration. It isnot easy to draw a conclusion about the coefficientC because of rather big uncertainties at a level of50 % as well as due to weak statistics. Anyway, wecan state that the annual average value C is at a levelof –26 m and the deviations are about 100 %.The variation with the period of 24 h can be regardedas the dominant one since its amplitude is 2.3times higher than the variation with the period of 12h. Finally, the values of the parameter j (y) oscillatearound the mean value 0.25p (0,9p) with the variationat a level of 100 % (55 %). From figures 7 and 8it is also obvious that the minimum of EMH is shiftedfrom 2:30 a.m. in summer to 8:30 a.m. in winterand depends fairly well on sunrise time.6,005,50h [m]12010080605,004,504,00ARn [Bq/m3].402001 2 3 4 5 6 7 8 9 10 11 12MesiachA Rn3,503,00Fig. 4 Annual course of coefficient A (10) for EMH and 222 Rn volume activity0-20hA Rn3,002,50h [m]-40-60-802,001,501,00ARn [Bq/m3].-1000,50-1201 2 3 4 5 6 7 8 9 10 11 12Mesiac0,00Fig. 5 Annual course of coefficient B (10) for EMH and 222 Rn volume activity