Frequency domain analysis of lightning protection using four lightning protection rods

In this paper the lightning discharge channel is modeled as a vertical monopole antenna excited by a pulse generator at its base. The lightning electromagnetic field of a nearby lightning discharge in the case of lightning protection using four vertical lightning protection rods was determined in the frequency domain. Unknown current distributions were determined by numerical solving of a system of integral equations of two potentials using the Point Matching Method and polynomial approximation of the current distributions. The influence of the real ground, treated as homogeneous loss half-space of known electrical parameters, expressed through a Sommerfeld integral kernel, was modeled using a new Two-image approximation which gives good results in both near and far fields

On the Choice of the Lightning Channel Current Decay Constant in the Modified Transmission Line Model with Exponential Decay

For different values of the decay constant in the Modified Transmission Line Model with Exponential Decay (MTLE) and for dierent channel heights the results for lightningelectromagnetic field (LEMF) at dierent distances fromthe channel-base are presented in this paper, so as for the spatial and temporal current distribution along the channel. The decay constant influence on LEMF above perfectly conducting ground is analyzed using new lightning channel-base current function and MTLE as an engineering model for a lightning return stroke. The proper choice of this constant can be made based on experimental results but also on the analysis of its influence on electric and magnetic field values and their shape characteristics

Comparative anatomical investigation of five Artemisia L. (Anthemideae, Asteraceae) species in view of taxonomy

Comparative anatomical analysis of vegetative organs has been conducted on Artemisia campestris L., A. absinthium L., A. arborescens L., A. judaica L. and A. herba-alba Asso, using light microscopy, in order to examine the most important anatomical features and to find new valid taxonomic characters. Results have shown that general root, stem and leaf anatomical features and nonglandular and glandular trichomes are shared by all species. However, some characters (parenchyma sheath, which surrounded vascular bundle and extended to both epidermises, subepidermal collenchyma and the absence of secretory canals in the leaves) link together A. absinthium and A. arborescens from the same section. Some characters, as periderm and lignified pith parenchyma cells (A. campestris and A. arborescens), nonendodermal secretory canals in root cortex (A. absinthium and A. judaica) and secretory canals in the leaf phloem (A. judaica and A. herba-alba), connect species belonging to different sections. Moreover, some characters could be considered as species-specific, nonendodermal secretory canals in the root secondary phloem, triangular leaf shape on the cross section and secretory canals in the leaf parenchyma for A. campestris, secretory canals in the stem pith for A. absinthium, crystals in the pith parenchyma cells for A. arborescens and the absence of root secretory canals for A. herba-alba. Given results revealed qualitative characters, on the basis of which the studied species are anatomically distinguishable between each other, provide valuable features for better species identification and contribute to the anatomy of the genus Artemisia

Supplementary material for the article: Rančić, M. P.; Stojiljković, I.; Milošević, M.; Prlainović, N.; Jovanović, M.; Milčić, M. K.; Marinković, A. D. Solvent and Substituent Effect on Intramolecular Charge Transfer in 5-Arylidene-3-Substituted-2,4-Thiazolidinediones: Experimental and Theoretical Study, 2016. https://doi.org/10.1016/j.arabjc.2016.12.013

Supplementary material for: [https://doi.org/10.1016/j.arabjc.2016.12.013]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/305

INFLUENCE OF DIFFERENT DISTANCE METRICS, ON EMERGENCY VEHICLES RELOCATION OPTIMIZATION PROCESS, BASED ON AUTOMATIC VEHICLE LOCATION DATA

In the implementation of the emergency vehicle dwelling location optimization process, different approaches in definition of the distances between two locations are possible. The distances can be treated as Euclidian, road network routed or time distances. The main question is how the choice of different type of distances used affects  the quality of the optimization solution. In this study, using the same data set and identical method, three different types of distances are used and the results are compared. For the purpose of comparison and evaluation of the quality of the obtained solutions, an innovative definition of a parameter named the saving ratio is proposed. On the basis of that parameter, quality of the obtained optimization solutions is quantified and estimated. In the previous works of the same authors, extensive algorithm to resolve the problem of p-median is designed. That algorithm, named GA-GISLAB, is used as a test bed optimization method. It performs relocation of vehicle resources in the road traffic based on the modified Genetic algorithm. Assessment of the impact of different types of distances to the quality of the optimization solution was performed using historical data from automatic vehicle location system