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Parametric Simulation Framework for Cycloidal Gear Actuators Using ANSYS and RecurDyn
No full textThis study introduces an integrated parametric simulation framework utilizing ANSYS and RecurDyn for the performance evaluation and design optimization of cycloidal gear actuators. The proposed framework synergizes Finite Element Analysis (FEA) and Multi-Body Dynamics (MBD) simulations, effectively overcoming the limitations inherent in traditional isolated analyses, where static stress distribution and dynamic behavior are typically modeled separately. Unlike conventional methods, which often lack flexibility and real-time adjustments, the hybrid approach presented in this paper enables automated parameter updates, significantly enhancing design optimization processes and fatigue life prediction accuracy. The methodology is comprehensively outlined, covering all stages from model generation and mesh refinement to load application and fatigue life prediction. This detailed workflow illustrates the framework's robust capability in simulating and optimizing gear performance. Additionally, a broad range of visual outputs, including contact stress contour plots, transmission error curves, and vibration frequency domain data, is provided, offering a holistic view of the system's performance. While the technical approach is thorough, this work identifies critical gaps in current simulation tools, specifically the lack of automation and integrated dynamic modeling. The proposed ANSYS-RecurDyn platform addresses these challenges, providing a flexible and efficient tool for real-time parameter adjustments. The framework's implementation has significant implications for applications in fields such as robotics, aerospace, and precision machinery, where high torque efficiency and fatigue reliability are essential
Analysis of the Effect of Wind Turbines Used In Electric Vehicles on Drag Power
No full textThe increasing role of electric vehicles (EVs) in future transportation systems is of significant importance for improving energy efficiency and environmental sustainability. The integration of renewable energy sources, particularly wind energy, with these vehicles has the potential to reduce energy costs and carbon emissions. This study analyzed how different wind turbine placements influence electric vehicles in terms of drag force. The aerodynamic performance impacts of various configurations were also examined. The drag force on the vehicle was determined based on the turbine location, and the optimal placement was identified. For this purpose, an electric vehicle model was designed, and simulations were conducted using ANSYS (Analysis Systems) software. Additionally, the amount of energy generated was compared with the energy loss caused by the increased drag force. Furthermore, the most efficient integration method for wind turbines in electric vehicles was determined
Design and Validation of a Rotational End-Effector with a Stalk-Bending and Separation Mechanism for Apple Harvesting
No full textTraditional gripping end-effectors often damage fruit due to structural complexity and uneven force distribution. To overcome these limitations, this study proposes a rotational end-effector that safely separates the stalk from the branch through a bending action. First, the design scheme and operating principle were established based on harvesting requirements. A rotational harvesting strategy was then formulated using statistical data, notably an average stalk length of 21.98 ± 4.33 mm. Subsequently, a composite mechanical model was developed, which enabled the derivation of critical conditions for stalk separation through theoretical analysis. Next, finite element simulations were conducted to assess the bending effects and stress distribution, confirming the end-effectorꞌs capability to protect the appleꞌs surface. Finally, the end-effector was integrated into a harvesting robot and underwent extensive field experiments. Key parameters such as motor torque, motor speed, and opening width were optimized using response surface methodology (RSM). Under conditions of a 31.43 rpm motor speed, 6.22 N·m motor torque, and a 34.16 mm opening width, the theoretical harvesting success rate reached 90.17%, while the actual success rate was 89%, demonstrating a negligible discrepancy. These results indicate that the rotational end-effector effectively preserves apple quality and holds promising prospects for practical application
Improving the Secondary Users' Quality of Service in Cognitive Radio Networks Using Partial Order Transfer Learning through Unused Channel Allocation
No full textUnused channel sensing and allocation in Cognitive Radio Networks (CRN) are streamlined using guard intervals to enhance the Quality of Service (QoS) of secondary users (SUs). Identifying the guard interval succeeding unused channels is tedious due to multi-interference and asynchronous resource allocations. To address this problem, the article introduces a Multi-Objective Optimization Scheme (MOOS) using Partial-Order Transfer Learning (POTL). The objectives are defined as interference minimization, optimal power utilization, and maximum channel allocation. These objectives are satisfied by untying the allocated channels that are close and away from the guard interval. The guard interval without overlapping channels is identified to reduce the allocation failures by mitigating the asynchronous intervals. The partial order derivatives are responsible for verifying the asynchronous overlap between the guard and unused channel allocation intervals. From this estimation, the overlapping and non-overlapping intervals are distinguished to improve the allocation with optimal power utilization. The transfer learning opts for the selection of a precise unused channel that satisfies maximum QoS objectives during SU response intervals. The proposed optimization scheme improves the channel allocation rate by 10.13%, power utilization efficiency by 10.5%, and network throughput by 12.03% for the maximum number of secondary user variants considered
Intelligent Detection of Road Rage Using PNN Parameter Optimization and Multimodal Driver Speech and Text Data
No full textRoad rage is a critical factor in traffic accidents, often expressed through vocal and semantic cues. This study proposes a multimodal road rage detection system that integrates speech and text features. Speech signals are processed by a probabilistic neural network (PNN) optimized with an Improved Sand Cat Swarm Optimization (ISCSO) algorithm, while text features are modelled with a long short-term memory (LSTM) network. A decision-level fusion strategy combines outputs from both modalities. Experiments on a self-constructed dataset of 10,000 speech samples and corresponding text corpora demonstrate that the proposed model achieves superior performance compared to CNN, DBN, TextCNN, and hybrid deep learning baselines. The system achieved maximum accuracy and recall of 95.61% and 99.31%, while maintaining low computational overhead (minimum detection time 58 ms, memory usage 10.06%). These findings suggest that the ISCSO-PNN and LSTM multimodal fusion framework provides an efficient and effective approach to detecting road rage, with strong potential for integration into real-time intelligent transportation systems
Dispersed conducting tissue fromthe Gzhelian (Saberian) of the Kounov Coal in the Kladno-Rakovník Basin, Czech Republic
No full textThe late Pennsylvanian Kounov coal seam yielded exceptionally well-preserved vascular elements. Their determination is questionable due to their fragmentary nature. Scalariform, reticulated and pitted tracheids prevail. They are comparable with the sphenopsid plants Arthropitys and Sphenophyllum. Some scalariform and reticulated tracheids also resemble those of ferns. However, their precise determination is not possible. Some uniseriate pitted tracheids resemble some conifers. Because conifers do not occur in coal, they might belong to secondary wood of some calamitaleans. Dispersed vascular tissues are correlated with dispersed cuticles and macrofossils
Trends and Networks in the Application of MCDM Methods in Computer Science: Analysis of the Web of Science Database
No full textThis paper presents a comprehensive bibliometric analysis of scientific output in the field of Multi-Criteria Decision-Making (MCDM) within the context of computer science, focusing on the period from 2019 to mid-2025. Using data from the Web of Science Core Collection, a total of 302 relevant papers were identified based on criteria such as publication year, language, document type, open access status, and research area. The analysis covers publication dynamics, the most influential authors and institutions, thematic directions, and collaboration structures. Special emphasis is placed on citation analysis of the most impactful works, as well as the visualization of co-authorship networks using the PRISMA methodology and tools such as RStudio and Biblioshiny. The results reveal a growing trend in publications, high activity by certain authors (e.g., Akram M and Liu Y), and strong collaboration within research clusters. Dominant topics include decision-making models, alternative selection, aggregation operators, and priority evaluation. This study provides insights into the structure and dynamics of the scientific community engaged in MCDM methods in computer science and may serve as a guide for future researchers, practitioners, and scientific development strategies
ANTUN GUSTAV MATOŠ AND THE YUGOSLAV QUESTION: A HISTORICAL-POLITICAL SCIENCE PERSPECTIVE
No full textU ovom sam radu pokušao istražiti kako je Matoš zapravo gledao na Srbiju i jugoslavensku ideju u burnim godinama prije Prvog svjetskog rata. Njegovi stavovi nisu bili neka fiksna teorija, oni su se stalno mijenjali pod utjecajem pravaštva, ali još više pod utjecajem onih deset godina koje je proživio kao emigrant u Beogradu. Nadasve su se mijenjali kroz njegov osobni doživljaj u datom trenutku. Kroz analizu i usporedbu radova Tomislava Jonjića i Nenada Prokića, rad pokazuje Matoša koji je stalno bio rastrgan. S jedne strane se divio srpskoj energiji, a s druge se smrtno bojao da će jugoslavenski projekt, ako se ostvari, progutati hrvatski identitet i državnost u korist Beograda. Cilj mi je bio prikazati Matoša ne kao nekakvog sustavnog političara, već kao borbenog polemičara čije pisanje najbolje ocrtava koliko su hrvatsko-srpski odnosi u to vrijeme bili zamršeni i puni emocija.In this paper I tried to explore how Antun Gustav Matoš actually viewed Serbia and the Yugoslav idea in the turbulent years before the First World War. His views were not some fixed theory; they were constantly changing under the influence of the Party of Rights ideology (pravaštvo), but even more under the influence of the ten years he spent as an émigré in Belgrade. Above all, they changed through his personal experience at a given moment. Through the analysis and comparison of the works of Tomislav Jonjić and Nenad Prokić, the paper presents Matoš as someone who was constantly torn. On the one hand, he admired Serbian energy, and on the other, he was deeply afraid that the Yugoslav project, if realized, would swallow Croatian identity and statehood in favor of Belgrade. My aim was to present Matoš not as some kind of systematic politician, but as a combative polemicist whose writing best illustrates how complex and emotionally charged Croatian-Serbian relations were at the time
Stjepan Brebrić, Kristologija u dogmatskoj teologiji Stjepana Bakšića, Kršćanska sadašnjost, 2025., 1067 stranica
No full textPrikaz knjige: Stjepan Brebrić, Kristologija u dogmatskoj teologiji Stjepana Bakšića, Kršćanska sadašnjost, 2025., 1067 stranic
Green innovations, stakeholder pressures and environmental performance in the hotel industry
No full textPurpose – This study investigates the mediating influence of green innovations on the
relationship between stakeholder pressures and environmental performance within the
Ghanaian hotel industry.
Methodology – A quantitative research approach was applied, gathering data from 273
hotel managers in Ghana. The analysis employed SPSS and Smart PLS software to assess
the relationships among stakeholder pressures, green innovations, and environmental
performance. Structural equation modeling (SEM) was used to test the hypotheses and
evaluate the mediation role of green innovations.
Findings – The study finds that green innovations significantly mediate the connection between
stakeholder pressures and environmental performance, highlighting that hotels addressing
customer and regulatory demands can better enhance their environmental outcomes when
incorporating green innovations. This study also points out a lack of research on stakeholder
and environmental dynamics within Ghana’s hospitality sector, addressing this gap.
Originality of the Research – This research contributes to both stakeholder and institutional
theory by illustrating the critical role of green innovations in helping hotels meet external
demands for sustainability. It offers new insights for academics and practitioners, emphasizing
proactive stakeholder engagement and sustainable practices as strategic advantages within the
hotel industry in Ghana