This paper presents a mathematical model for the selection of an optimal power cable conductor cross section and the dimensions of a corrective backfill. To this end, a detailed model for the calculation of the life-cycle cost of cable ownership is presented. The formula considers the material and labor costs in the production of a power cable as well as the cost of losses during its operation. Simultaneously, the procedure seeks the optimal size of the corrective backfill, taking ampacity constraints into account. Since the formulation is complex, a genetic algorithm is proposed to solve the optimization problem. A real-life numerical example is presented.

Objectives: Atmospheric pressure is the most objective weather factor because regardless of if outdoors or indoors it affects all objects in the same way. The majority of previous studies have used the average daily values of atmospheric pressure in a bioclimatic analysis and have found no...

Aim of this study was to assess concentrations of interleukin-6 (IL-6), interleukin-8 (IL-8) and interleukin-18 (IL-18) in the serum of newborns with diagnosed intrauterine growth restriction (IUGR) in comparison to concentrations in serum of newborns with weight appropriate for gestational age (AGA). Research was conducted at the Lodz Medical University Clinic of Neonatology during 2010-2011. Surveyed group consisted of 50 hypotrophic full-term infants of single pregnancies (average weight: 2329 ± 287 g); control group, enclosing 50 infants AGA (average weight: 3544 ± 2161 g). Both groups received average Apgar score of 9 points. Concentrations of analysed cytokines were marked between 4-6 hours after birth. The enzyme-linked immunosorbent assay (ELISA) test was used to determine interleukins concentrations. Study was prospective. Statistics on the data were conducted with the Kolmogorov-Smirnov test. Significance level: p < 0.05. Concentrations of IL-6 and IL-18 were elevated in the IUGR group in a statistically significant manner in comparison to the control group. An elevated level of IL-6 and IL-18 in the IUGR group, comparing to control group, signifies the existence of inflammation in the process of developing IUGR, therefore, screening tests estimating levels of interleukins as IL-6 and IL-18 might be clinically useful in predicting the occurrence of IUGR and help preventing it.