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Developing the measurement scale for organizational resilience assessment based on IMF SWARA method
No full textThe purpose of this research is to develop a novel conceptual framework for organizational resilience measurement, based on the employees’ assessment on different managerial levels. The methodology of research is based on the questionnaire survey that is enabling the technological, human, organizational and sustainability factors assessment in industrial organizations, operating in Serbia and Montenegro. Obtained survey results were further processed with the reliability analysis and discriminant validity check of proposed measurement scales and analyzed by applying the IMF SWARA method from the perspective of four identified resilience corners: anticipate, monitor, react and learn. Organizational resilience was calculated separately based on the survey collected among the middle and top-level managers in investigated organizations. The highest resilience coefficients, based on the middle level managers’ assessment, are obtained regarding their observation of the organizational performance (4.8), motivation of employees regarding safety and health at work (4.7) and organizational growth and business profitability (4.7) while the lowest value was observed regarding working environment conditions (3.9). In case of the top-level managers’ assessment, the highest resilience coefficients are also calculated regarding motivation of employees regarding safety and health at work (4.7), followed by knowledge of occupational safety (4.6), associate support (4.6), support from superiors (4.6) and management commitment (4.6). The lowest value, for this group of respondents, was also observed related to the working environment conditions (4.1), which appears to be the weakest influencing factors, from the point of view of both management structures. When it comes to observed resilience corners, the “monitor” corner should be substantially improved, being with the lowest resilience indicator, assessed by the both groups of management structures (4.29 and 3.05, for the middle and top level managers, respectively). The highest level among the resilience corners, for the case of middle level managers was observed for the “anticipate” (4.43) and “react” (4.43), while in the case of the top-level managers, again it was the “react” corner (4.61). The originality of this research is in systematical approach to organizational resilience measurement, using the novel measuring scale proposed here in combination with different MCDA methods and techniques
Kinematic Modeling of the End-Effector of a Plum-Picking Robot Using the Rodrigues’ Rotation Formula
No full textThis paper presents the kinematic analysis of a designed end
effector for a plum-picking robot. The study includes solving both the
direct and inverse kinematics problems to determine the position and ori
entation of the gripper relative to the end-effector’s base. The kinematic
analysis is performed using Rodrigues’ transformation formula, ensuring
an accurate representation of rotational motion. All robot parameters
are derived from the designed model in SolidWorks, providing a realis
tic basis for the mathematical model. In addition, a workspace analysis
is performed to evaluate the reachability and efficiency of the robotic
system in the fruit picking process. The results obtained offer insight
into the capabilities of the system and contribute to the optimization of
robotic harvesting by ensuring precise motion control.451-03-137/2025 03/200105 from 04.02.202
Preliminary Mission Specifications of MOSAIC Satellite
No full textNano satellites, also known as nano-sats, are small satellites that typically weigh less than 10 kg. Here, we present CubeSat, a class of nano-sats, that consists of one or more “cubes” that form the satellite structure where platform and payload equipment is to be placed. This paper discusses preliminary mission specifications as a first step of designing MOSAIC (Multi-purpOSe AcademIc Cubesat). MOSAIC is to be the first Serbian scientific CubeSat satellite with ambitious technological, scientific and educational goals. The specifications include satellite power, mass and link budgets, and the technical documentation for the mission payload
Artificial Intelligence-Supported Shape Optimization of an Automotive Rubber Bumper
No full textIn rubber bumper design, the most important mechanical property of
the product is the force-displacement curve under compression and its
fulfillment requires an iterative design method. Design engineers can
handle this task with the modification of the product shape, while the
axisymmetric finite element model of the rubber product is an
efficient way to evaluate the working characteristics. Using an
optimization process in place of a trial-and-error-based mechanical
engineering design method can help a company stay competitive in
the market if the iteration process can be automated
Optimization of Phasor Data Concentrators (PDC) Placement and Communication Infrastructure in Power Systems for Cost-Effective Management
No full textThis paper presents a study on optimizing the placement and required number of Phasor Data Concentrators
(PDCs) to enhance power system management efficiency. With the increasing deployment of Phasor
Measurement Units (PMUs) in power networks for real-time monitoring, efficient data aggregation through
strategically placed PDCs is essential. This research aims to determine the optimal locations for PDCs while
minimizing the overall costs of building the communication infrastructure necessary for data transfer
between PMUs and PDCs. This is very significant nowadays, as the costs of building communication
infrastructure are considerably higher than the prices of PMU devices.
The proposed approach employs advanced optimization techniques, such as genetic algorithms, to analyze
various configurations and assess cost-effectiveness. By incorporating constraints related to the power
network topology, data transmission latency, and reliability, the study identifies cost-optimized locations
that ensure robust system observability and resilience. The methodology also examines the communication
paths to minimize delays and improve data accuracy.
Key findings demonstrate that optimized PDC placement not only reduces infrastructure expenses but also
enhances the speed and reliability of data collection and processing within power systems. The results
provide valuable insights for power system operators in real time and network planners, highlighting the
economic and operational advantages of strategically configured PMU-PDC setups
Time Minimization During Simultaneous Longitudinal and Rotational Motion of a Chaplygin Sleigh
No full textThe problem of minization of the time of motion of a Chaplygin sleigh in the horizontal
plane is analyzed. The force directed along the linear velocity vector and the torque are considered as
control inputs. The use of the Pontryagin maximum principle allows for establishing that three types
of control are possible: regular control, taking the boundary values (bang-bang) for the force and the
torque, first-order singular control for the force, and second-order singular control for the torque. If
the control is singular for the force on the entire interval, the solution of the optimization problem is
not unique. The second-order control segment can be connected with nonsingular control only by
means of the “chattering” regime. A simpler suboptimal control is proposed that contains a finite
number of switchings. Examples are considered for the specified end states and partially specified end
states. Analysis of possible combinations of singular and regular arcs of the trajectory is performed.Ruska verzija rada:
А. Обрадовичa, Ю. Д. Селюцкий , О. Ю. Черкасов,МИНИМИЗАЦИЯ ВРЕМЕНИ ПРИ ОДНОВРЕМЕННОМ
ПРОДОЛЬНОМ И ВРАЩАТЕЛЬНОМ ДВИЖЕНИИ КОНЬКА ЧАПЛЫГИНА,ИЗВЕСТИЯ РАН. ТЕОРИЯ И СИСТЕМЫ УПРАВЛЕНИЯ, 2025, № 5, с. 47–6
INFLUENCE OF LAYER HEIGHT ON CAVITATION RATE OF 3D-PRINTED PLA
No full textThis study investigates the cavitation erosion behaviour of PLA (polylactic acid) specimens fabricated by Fused Deposition Modelling (FDM) using different layer heights (0.1, 0.2, and 0.3 mm). The samples were exposed to cavitation at a frequency of 20 ± 0.5 kHz for 60 and 120 minutes. Visual inspection revealed that smaller layer heights resulted in finer surface morphology, better interlayer bonding, and improved resistance to cavitation. After 60 minutes, slight surface roughening and local delamination were observed in all samples, while after 120 minutes, surface degradation became more pronounced, especially for larger layer heights. Samples printed with a 0.1 mm layer height mainly exhibited plastic deformation and minor delamination, those with 0.2 mm showed a combination of plastic deformation and delamination, whereas the 0.3 mm specimens were dominated by large-scale detachment and severe surface damage. The cavitation rate diagram, obtained from mass loss measurements, confirmed these observations. The lowest mass loss rate (0.77 mg/min) was recorded for the 0.1 mm samples, while the highest rate (1.50 mg/min) corresponded to the 0.3 mm samples. The results demonstrate that increasing layer height significantly reduces the cavitation resistance of FDM-printed PLA due to weaker interlayer cohesion and higher surface roughness.451-03-137/2025-03/200105, 451-03-136/2025-03/200135, 451-03-136/2025-03/20028
The role of AI in architecture: fantasies and reality
No full textThe field of artificial intelligence (AI) has recently attracted the attention of many disciplines due to the exceptional accomplishments and rapidly emerging possibilities. Architecture, a discipline traditionally skeptical of new technologies, is intrigued by the results achieved with generative neural networks.
The emergence of new technologies in the field of generative artificial intelligence has led to numerous scenarios among architects about possible applications of these technologies in their practice. A large number of these scenarios are based on the functionality of commercially available Large Language Models and their application to text to image and image to image transformations. A smaller number of scenarios are based on specific applications of AI technologies through the development of real software solutions. The paper critically analyzes existing scenarios through a review of existing research and a description of software solutions. The focus is on the application of Generative Neural Networks and the paper provides an overview of the functioning of the basic classes of neural networks that make up this technology.
An analysis of how artificial neural networks work shows that they all depend on the data set used to train them. Today's neural networks use an enormous amount of data, but even that is limited to what is available in electronic format. The main source of general knowledge is online encyclopedias, while expert knowledge is provided by published articles that have a certain level of reliability. Architects who are mistrustful of this technology need to understand that better results can only be achieved through higher-quality training data sets and that their protectively guarded knowledge also comes from studying the work of other architects
Additive Manufacturing: A Key to Advancing Injection Molding Efficiency
No full textThe increasing demand for custom-made products, small-batch production, and improved process efficiency is driving manufacturers to adopt advanced strategies that minimize costs and production time. Additive manufacturing (AM) technologies address these challenges by enabling rapid prototyping, design flexibility, and advanced tooling capabilities. Initially constrained to polymeric prototypes, AM now supports a diverse material range, including metals and temperature-resistant polymers. Injection molding is a widely used manufacturing process for producing plastic parts with high precision and repeatability. However, traditional injection molding faces challenges such as high tooling costs, long lead times, and design limitations. This paper investigates solutions to these challenges through the application of additive manufacturing and rapid tooling technologies, emphasizing their potential to transform efficiency in injection molding
OPTIMIZATION OF THE DELTA 3D PRINTER STRUCTURE
No full textIn recent years, additive manufacturing technologies have made significant progress in terms of structural solutions, printing parameters, materials, and software support. This paper presents the process of reconstructing and optimizing a damaged and non-functional Delta 3D printer, with the goal of making it suitable for use in an educational setting. A Delta 3D printer is a type of additive manufacturing system distinguished by its unique kinematic structure, where three vertical arms are arranged in a triangular base configuration and simultaneously control the printhead's position. This design enables high-speed operation, precise movement, and fabrication of models with significant height. This configuration is particularly advantageous in educational environments, as it illustrates the diversity of 3D printer mechanisms and underlying engineering principles. Using reverse engineering methods and modern additive manufacturing technologies – FFF (Fused Filament Fabrication) and SLA (Stereolithography), damaged and worn-out components were replaced and certain technical improvements were implemented. The reconstruction involved replacing key components and improving the printer’s functionality and ease of use, making it more suitable for educational purposes. After the reconstruction, the device was successfully tested and is now capable of reliably producing functional models. The printer is operated using Marlin firmware and the Arduino