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Wed, 02 Sep 2026 09:06:14 GMT 2026-09-02T09:06:14Z https://scidar.kg.ac.rs/handle/123456789/23273 Title: IT-Based Feasibility Assessment of a Shallow Geothermal System in a Renovated Educational Building in Kragujevac Authors: Nastić, Filip; Živković, Dubravka; Končalović, Davor; Vukasinovic, Vladimir; Josijevic, Mladen; Gordić, Dušan Thu, 01 Jan 2026 00:00:00 GMT https://scidar.kg.ac.rs/handle/123456789/23273 2026-01-01T00:00:00Z https://scidar.kg.ac.rs/handle/123456789/23272 Title: AN ESL–HSDT FINITE ELEMENT MODEL WITH A VARIATIONAL EXPONENTIAL THICKNESS FUNCTION FOR THERMO-MECHANICAL ANALYSIS OF COMPOSITE PLATES Authors: Radakovic, Aleksandar; Čukanović, Dragan; Bogdanovic, Gordana; Knežević, Petar; Milenković, Strahinja; Nešović, Aleksandar Abstract: This paper presents a novel finite element formulation for the thermo-mechanical bending analysis of orthotropic and laminated composite plates, developed within the framework of an equivalent single-layer higher-order shear deformation theory (ESL–HSDT). In contrast to conventional higher-order models, which rely on predefined polynomial approximations through the thickness and thereby limit the physical accuracy of shear representation, the proposed approach introduces an exponential thickness shape function whose governing parameter is determined through a variational criterion, reducing the arbitrariness associated with predefined through-thickness functions and providing a physically grounded representation of transverse shear deformation. By directly linking the kinematic assumptions to the through-thickness distribution of transverse shear deformation, the formulation ensures a smooth and mechanically consistent prediction of deformation and stress distributions without the need for shear correction factors. The model is implemented using a four-node quadrilateral finite element with seven degrees of freedom per node, thus maintaining high computational efficiency while preserving higher-order kinematic accuracy. The accuracy and robustness of the proposed formulation are validated through a series of benchmark problems involving orthotropic and laminated plates subjected to both uniform and spatially varying thermal loads, as well as mechanical loading. The results show good agreement with reference solutions from the literature and three-dimensional elasticity theory, with small deviations for global response quantities and larger discrepancies observed only for local transverse shear stresses, which is consistent with the expected behaviour of ESL formulations. Compared to classical and layerwise approaches, the proposed model achieves a comparable level of accuracy while significantly reducing computational cost, demonstrating that the adopted thickness function effectively captures interlaminar shear effects within an equivalent single-layer framework. The developed formulation provides a robust and computationally efficient tool for the analysis of composite plates under coupled thermo-mechanical loading and establishes a physically motivated basis for the further development of advanced through-thickness modeling strategies. Thu, 01 Jan 2026 00:00:00 GMT https://scidar.kg.ac.rs/handle/123456789/23272 2026-01-01T00:00:00Z https://scidar.kg.ac.rs/handle/123456789/23271 Title: The Influence of Microstructure on the Hardness of Car Brake Discs Authors: Suhi, Slaven; Milojević, Saša; Marić, Dejan; Šolić, Tomislav; Deanović, Iva Abstract: Various exploitation influences and the resulting abrasion, erosion or other forms of corrosion destruction can greatly cause changes in the microstructure of car brake discs, thereby reducing their service life and reliability. Due to its properties, gray cast iron is mostly used for conventional car brake discs and as such is subject to the negative influences of the previously mentioned factors. In order to assess this influence and numerically relate it to the actual condition of the discs in operation, the hardness and microstructure of used car brake discs divided into three groups were measured. An analysis of hardness measurement results was conducted alongside micrographs. The findings are presented graphically, with discussions on how microstructure influences hardness and how changes in microstructure affect the hardness of car brake discs. By analyzing microstructure imaging, it can be concluded that different groups of brake discs exhibit varying microstructures. In addition, it was found that there are significant changes in the measured hardness of discs with different operating cycles. The test results should contribute to the optimization of material production processes. The research findings presented in this study could help in proper brake disc maintenance and determining optimal service intervals for replacement. Thu, 01 Jan 2026 00:00:00 GMT https://scidar.kg.ac.rs/handle/123456789/23271 2026-01-01T00:00:00Z https://scidar.kg.ac.rs/handle/123456789/23270 Title: OPTIMIZATION OF DRIVE-IN RACKING STORAGE SOLUTION Authors: Vujanac, Rodoljub; Miloradović, Nenad; Piskulić, Mirjana Abstract: Drive-in and/or drive-through racking systems with adequate principle of functioning, as the most common high density storage solution, usually find applications in pharmaceutical, chemistry and food industry. Since the goods are stored into the deep tunnels, traditional aisles are eliminated for manipulation purposes like in the adjustable pallet racking configurations. The main prerequisite for the usage of this type of storage is that the goods must be palletized on the standard and quality pallets. Materials used for the rack structures are light cold-formed profiles. In this paper solutions in terms of the application of different pallet dimensions and its weight were discussed. On the basis of techno-economical analysis of several options, the best solution in term of relation price for the total number of pallets or mass of stored goods will be suggested to the user. Wed, 01 Jan 2025 00:00:00 GMT https://scidar.kg.ac.rs/handle/123456789/23270 2025-01-01T00:00:00Z