SCIDAR - Дигитална архива Универзитета у Крагујевцу

Over the past few decades, there has been a noticeable increase in global energy consumption, which represents a significant problem caused by unsustainable and harmful methods of energy production. This issue leads to an emission of harmful greenhouse gases and environmental pollution on a global scale. By considering the reasons that lead to the mentioned problems, emphasis has been placed on the technologies of the renewable energy sources, as a key solution for reducing harmful environmen...

This paper presents a Multi-Criteria Decision-Making (MCDM) framework for the evaluation and ranking of industrial punch presses based on their operational performance. The case study was conducted in a company engaged in the production of industrial machines and assemblies. For the first time, the Square-Root based Evaluation Method (SREM) is introduced and applied, aiming to overcome certain limitations of MCDM methods based on linear data normalization. The SREM method introduces a combine...

In this study was investigated the fracture of the welded supporting structure of a satellite carrier of a bucket wheel excavator drive reducer. The research was aimed at identifying the root causes of the failure through an integrated failure analysis combining theoretical calculations, numerical modelling and experimental investigations. The loading analysis included digging resistance, natural and forced oscillations of the excavator structure, and verification of the support strength unde...

This study investigates the enhancement of AA6082/Al2O3 aluminum metal matrix nanocomposites (AMMNCs) through powder metallurgy combined with systematic process optimization. Ultrasound-assisted dispersion and Taguchi design L9 orthogonal array were employed to improve nanoparticle distribution and optimize fabrication parameters. The effect of Al2O3 content and ultrasonication time (UT) on hardness and compressive strength was analyzed using S/N ratio and ANOVA. Characterization was performe...

Calibration of heat-source parameters and boundary heat losses is essential for reliable numerical welding simulations. This paper applies Grey relational analysis with entropy-based weighting to calibrate a three-dimensional heat-transfer model for gas metal arc welding of P355GH steel. Eight parameters are calibrated simultaneously: five describing the Goldak double-ellipsoidal heat source and three describing convective and radiative losses. Latin hypercube sampling with 80 combinations i...

Local chicken breeds are increasingly being reconsidered as a means to produce distinctive meat in non-conventional systems while also supporting the conservation of endangered genetic resources. This study compared Banat Naked Neck (BNN) and Svrljig hen (SH), two Serbian indigenous breeds, reared under identical pasture-based conditions and slaughtered at 12 or 14 weeks. Carcass traits, including linear measurements and carcass composition, were evaluated in 40 males (10 per breed per a...

The Reprint Symmetry in Process Optimization presents a curated co lection of peerreviewed contributions that demonstrate the role of symmetry principles in enhancing optimization methods across multiple scientific and engineering domains. The included studies cover theoretical developments, algorithm design, and practical applications, including scheduling, machine learning, additive manufacturing, control systems, and decision making. By integrating symmetry concepts with modern optimizatio...

Existing methods for selecting the number of teeth in complex planetary gear systems are often methodologically demanding. They do not always ensure all conditions required for proper operation and assembly. This paper presents an analytical methodology for determining gear tooth numbers. The method is demonstrated on a Ravigneaux planetary gear set with seven kinematic links and two degrees of freedom. It ensures the simultaneous satisfaction of all meshing and assembly conditions. Starting ...

Cruise ships and superyachts have experienced significant global expansion throughout the 21st century. Although the growth in cruise passenger numbers was temporarily disrupted by the COVID-19 pandemic, occupancy rates have since rebounded and even exceeded pre-pandemic levels. This study highlights the significant environmental impact of cruise ships and luxury yachts, particularly in terms of air emissions and marine pollution. Emission levels associated with different fuel types and marin...