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Prevailing climatic conditions and local topography can be classified as the most influential environmental factors that affect the spatial dispersion of pollutants emanating from industrial sources. In this study, the combined effects of these factors were considered with respect to terrain exposure in order to explain the complex spatial trend of Arsenic (As) concentration that was atmospherically-deposited from one of the largest Copper Mining and Smelting Complexes in Europe, Bor in Serbia. Several exposure parameters were created and employed as spatial covariates within the so-called “Spline-Then-Krige” approach for producing maps of As concentration at three standard soil depth layers (0–5 cm, 5–15 cm and 15–30 cm). The exposure parameters were created to quantify two different aspects of terrain exposure: Geometrical (Proximity) and Topographical exposure. Regression analysis confirmed the presence of a significant statistical association between the As data and all exposure parameters. The trend model showed good overall accuracy explaining 52% of the variance in As data for the surface soil layer, 49% for the middle layer and 35% for the deepest layer. Relative importance analysis revealed the importance of considering a more general model that includes interactions between exposure parameters. The kriging interpolation improved, to some extent, the regression accuracy for all three layers with R2 values ranging from 55% for the surface layer to the 36% for the deepest soil layer. The prediction maps show that As contamination levels are well above allowable Serbian agricultural concentration limits (As < 25 mg/kg) for approximately 78% of the mapping area, thereby indicating that long term smelting activity leaves significant consequences on soil even on deeper unexposed layers. Journal of Geochemical Exploration (2017), 179: 25-35

Paper will present basic definitions and significance of implementation of information systems for facility maintenance, as well as terms Facility management (FM) and FM lifecycle. The main focus of this paper is on CAD and GIS integration within ArcGIS software in order to consolidate different data formats for creating unique information system for FM.

This paper presents the procedure for dynamic system identification regarding behaviour of bridge pylon for test load, and the numeric example had been illustrated by examination of ''Sloboda'' bridge in Novi Sad. Since pylon shifts, occurred during test load, were long-period in nature, static GPS method had been applied for measurements. To identify dynamic process of the construction, auto-regression model with external input (ARX) had been selected. The process had been approximated as linear and non-linear. Establishing model degree had been performed by autocorrelation function and parameter significance test. It had shown that the shifts of pylon along the longitudinal axis of the bridge, occurring due to the load action, must be described as a result of non-linear process; while shifts, occurring orthogonal to longitudinal axis of the bridge, occurring due to the temperature change, are the result of linear process. Model fitting was also analyzed, observing the pylon as both rigid and deformable body. Higher percentage of fitting (alignment) had been achieved when the construction had been viewed as a deformable body., U radu je opisan postupak identifikacije dinamičkog sustava ponašanja pilona mosta na probno opterećenje, a brojčani primjer ilustriran je ispitivanjem mosta „Slobode“ u Novom Sadu. Kako su pomjeranja pilona pri probnom opterećenju dugoperiodična, za mjerenja je primijenjena statička GPS metoda. Za identifikaciju dinamičkog procesa konstrukcije izabran je autoregresijski model s vanjskim pobuđivanjem (AutoRegressive with eXternal input – ARX). Proces je aproksimiran kao linearan i nelinearan. Za utvrđivanje stupnja modela primijenjena je autokovarijacijska funkcija i test značajnosti parametara. Pokazano je da se pomjeranja pilona mosta, u smjeru duže osi, koja nastaju pod utjecajem opterećenja, moraju opisati kao rezultat nelinearnog procesa; dok su okomita pomjeranja, koja nastaju uslijed promjene temperature, rezultat linearnog procesa. Također je analizirano fitovanje modela (suglasnost) kada je pilon promatran kao kruto i kao deformatibilno tijelo. Ostvaren je veći postotak fitovanja kada je pilon promatran kao deformatibilno tijelo.