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Dynamic Analysis of Micromobility In-Wheel Suspension System – Enhancing Safety in Urban Environments
No full textMicromobility has emerged as a major global trend in urban transportation. However, it has also led to a rise in accidents, largely attributed to improper usage and inadequate safety precautions. This paper presents a model developed for the dynamic analysis of an in-wheel suspension system for micromobility vehicles, along with proposals for its improvement. The model accounts for challenges related to urban infrastructure, particularly variation in various obstacle types and heights on cycle road pavement, using the city of Vilnius (Lithuania) as a case study. The research paper additionally evaluates factors affecting rider safety and risk, with a primary focus on in-plane dynamics. The dynamic analysis demonstrates that the in-wheel suspension system enhances riding safety across simulated variations. These findings help identify critical vertical dynamic risks for micromobility in urban area and offer insights for future city’s road infrastructure planning
Proposal for a Blockchain-Based Model for Data Management in Maritime Education and Sector Stakeholder Institutions
No full textBlockchain technology is increasingly proving to be an innovative solution in numerous spheres of the economy, including education, and by extension, institutions involved in Maritime Education and Training (MET). As MET institutions face increasing challenges, such as managing and maintaining large databases, extensive record-keeping, and exchanging and processing information, the application of this technology is emerging as a response to these challenges. In addition to the fact that it would lead to the digitalisation of documents, the application of the technology would, above all, improve the security and reliability of documentation. Owing to its decentralised, transparent and immutable nature, blockchain technology offers a comprehensive framework for overcoming these challenges within MET institutions. The objective of this paper is to propose a model for the application of blockchain technology in MET institutions in order to address the lack of a unified, secure and transparent data system shared by all stakeholders involved in maritime education and training. This paper provides a comprehensive review of the literature on the application of blockchain technology in the maritime industry, highlighting its potential for improving data management and operational efficiency. Furthermore, the paper proposes the implementation of blockchain technology, focusing on the creation of an integrated database that would be used by various users, including MET institutions, state administration (ministries, port authorities), seafarer training centres, maritime agencies, medical institutions and seafarers themselves. Moreover, the paper offers detailed recommendations and guidelines for implementing the hybrid model in MET institutions, with a special emphasis on its role in automating administrative processes through smart contracts, enhancing transparency, and improving overall document security
Research on Risk Factors Affecting High-Speed Railway Delays in China Based on Association Rules
No full textThis study aimed to investigate the contributing factors to high-speed railway (HSR) delays and their interdependency in China. A total of 420 records of high-speed railway delays in China were collected, and 15 risk factors related to high-speed railway delays were extracted. Descriptive statistics were used to illustrate the causes of HSR delays in terms of device, personnel and environmental conditions. The association rule mining technique was further applied to explore contributing factors that cause HSR delays, revealing the underlying mechanisms of delay occurrence. The results show that HSR delays of more than 1 hour are most likely caused by foreign objects hanging on the catenary. Moreover, 65% of HSR delays are within the range of 9–30 minutes. Among delay events with durations of 9 to 30 minutes, about 9% of are caused by the fault of on-board train control equipment, mainly the Automatic Train Protection (ATP). Regarding short delays of HSR within 8 minutes, the most likely cause is platform screen door faults, followed by traveller’s misconduct and train door faults. This study offers transportation agencies insights into HSR delay causes and aids in developing policies and engineering measures to reduce delays
Information-Enhanced Heterogeneous Graph Convolutional Networks for Multi-Source Data Fusion in the SiC Semiconductor Industry
No full textThe rapid expansion of the silicon carbide (SiC) semiconductor industry has created vast and heterogeneous data streams from academic publications, patents, technical standards, and market reports. Traditional methods struggle to integrate these multi-source datasets, limiting their ability to reveal technological trends and innovation pathways. To address this challenge, we propose an Information-Enhanced Heterogeneous Graph Convolutional Network (ie-HGCN) framework for multi-source data fusion in the SiC semiconductor electronic information industry. The method combines principal component analysis and random forest algorithms for feature extraction with a DeepGCNs-Att architecture augmented by self-attention mechanisms, enabling the effective modeling of complex relationships among heterogeneous data entities. Experimental results show that ie-HGCN outperforms conventional deep learning and graph-based baselines, achieving 88.63% accuracy, 90.65% precision, 87.54% recall, and an F1-score of 85.68%. A case study on patents and publications demonstrates the framework’s ability to identify emerging hotspots, such as advanced power module packaging, and to uncover novel industry-academia collaborations. These findings highlight the practical value of ie-HGCN as a robust tool for strategic R&D planning and technology forecasting in the SiC semiconductor domain
A Novel Adaptive Pitch Angle Control to Enhance Wind Farm Power Management
No full textThe role of wind farms in primary and secondary frequency control has become paramount for ensuring grid stability. This study proposes an adaptive PI control strategy sensitive to the grid Rate of Change of Frequency (ROCOF). The model under discussion involves using a control system that allows wind turbines to maintain a specific power reserve by implementing a de-loading strategy. This, in turn, enables the turbines to respond more rapidly and effectively to variations in frequency. The adaptive PI controller dynamically updates the PI gains using the grid frequency variation rate, thus allowing the power generation to adapt to grid conditions in real-time. Tests conducted in the MATLAB/Simulink environment demonstrate that the proposed adaptive control method provides enhanced dynamic performance compared to conventional PI control and substantially improves grid frequency regulation. The findings underscore the necessity for advanced control strategies to facilitate the integration of wind farms into active frequency control
UČINCI POREZNIH OLAKŠICA NA ISTRAŽIVANJE I RAZVOJ U SLOVENIJI
No full textThe paper investigates the effect of tax incentives on R&D expenditure in Slovenian firms, differentiating the impact by firm size and age. As there is a lack of empirical research on the effectiveness of these reliefs in Slovenia, and the research uses administrative firm-level data and an innovative approach, this study makes an important contribution to the literature. The effectiveness of the R&D tax incentives is based on the direct approach. The effect is identified by applying a quasi-experimental approach and the use of the difference-in-differences method. To rule out the effect of concurrent factors that could influence the level of R&D expenditure at the firm level, the paper uses the variation in regional tax relief rates. The paper finds that a one percentage point increase in the R&D tax relief was associated with a 0.571 percentage point increase in firms' R&D expenditure. The impact was larger for smaller and younger firms.Ovaj rad analizira učinak poreznih poticaja na izdatke za istraživanje i razvoj (I&R) u slovenskim poduzećima, s naglaskom na razlike u učinku s obzirom na veličinu i starost poduzeća. S obzirom na nedostatak empirijskih istraživanja o učinkovitosti tih poticaja u Sloveniji te korištenje administrativnim podacima na razini poduzeća i inovativnog pristupa, ovo istraživanje predstavlja važan doprinos znanstvenoj literaturi. Učinkovitost poreznih poticaja za I&R ocjenjuje se primjenom izravnog pristupa. Učinak se identificira korištenjem kvazieksperimentalnom metodom, konkretno, metodom razlika-u-razlikama. Kako bi se isključio utjecaj istodobnih čimbenika koji bi mogli utjecati na razinu izdataka za I&R na razini poduzeća, rad se koristi varijacijama u regionalnim stopama poreznih olakšica. Rezultati pokazuju da je povećanje porezne olakšice za jedan postotni bod povezano s povećanjem izdataka za I&R od 0,571 postotnog boda. Učinak je bio izraženiji kod manjih i mlađih poduzeća
IMPLIKACIJA COVID-19 PANDEMIJE NA DIGITALNO OBRAZOVANJE: SUSTAVNI PREGLED LITERATURE
No full textThe aim of this study is to assess the current state of digital education by identifying differences between blended and traditional learning models, examining the impact of the COVID-19 pandemic on digital education, and determining which multimedia and digital tools are used in the learning process. A systematic literature search was conducted using PRISMA guidelines, resulting in the selection of 50 open-access peer-reviewed articles published between 2007 and 2022. The studies were analyzed using MAXQDA software and synthesized into three thematic categories aligned with the research questions. Findings show that digital education is becoming an indispensable component of modern pedagogy, promoting interactive and intuitive learning experiences. Tools such as gamification, virtual reality, and multimedia platforms enhance student engagement, collaboration, and creativity. Nevertheless, challenges persist, including limited infrastructure and low digital literacy in under-resourced contexts. The study contributes to the field by offering practical insights and recommendations for educators, policymakers, and researchers striving to build inclusive and sustainable digital learning environments.Cilj je istraživanja procijeniti trenutno stanje digitalnog obrazovanja identificiranjem razlika između hibridnih i tradicionalnih modela učenja ispitivanjem utjecaja pandemije COVID-19 na digitalno obrazovanje te utvrđivanjem multimedijskih i digitalnih alata koji se koriste u procesu učenja. Sustavno pretraživanje literature provedeno je korištenjem PRISMA smjernicama, što je rezultiralo odabirom 50 recenziranih članaka s otvorenim pristupom objavljenih između 2007. i 2022. godine. Istraživanja su analizirana s pomoću softvera MAXQDA i grupirana u tri tematske kategorije usklađene s istraživačkim pitanjima. Nalazi pokazuju da digitalno obrazovanje postaje neizostavna komponenta moderne pedagogije, promičući interaktivna i intuitivna iskustva učenja. Alati kao što su gemifikacija, virtualna stvarnost i multimedijske platforme poboljšavaju angažman studenata, suradnju i kreativnost. Unatoč tome, izazovi i dalje postoje, uključujući ograničenu infrastrukturu i nisku digitalnu pismenost u kontekstima s nedovoljno resursa. Istraživanje doprinosi ovom području nudeći praktične uvide i preporuke za edukatore, kreatore politika te istraživače koji teže izgradnji uključivih i održivih okruženja za digitalno učenje
KOMPARATIVNA ANALIZA UTJECAJA FISKALNE POLITIKE NA ODRŽIVI RAZVOJ UKRAJINE I HRVATSKE
No full textThe paper presents a comparative analysis of fiscal policy impacts on sustainable development in Ukraine and Croatia. It introduces an integrated tax index combining economic, social, and environmental indicators to assess fiscal effectiveness. Using statistical data from 2017–2024 and forecasts for 2025, regression and index analysis methods to evaluate the dynamics of tax revenues, GDP, and tax burden has been applied. The findings reveal significant volatility in Ukraine’s fiscal indicators due to the war, while Croatia demonstrates gradual recovery and stability aligned with EU standards. The developed index enables cross-country comparison and identifies priority areas for policy reform. Results highlight that Croatia's experience offers practical insights for improving Ukraine's fiscal sustainability during post-war recovery.Rad predstavlja komparativnu analizu utjecaja fiskalne politike na održivi razvoj u Ukrajini i Hrvatskoj. Uvodi integrirani porezni indeks koji kombinira ekonomske, društvene i pokazatelje okolišne održivosti za procjenu fiskalne učinkovitosti. Koristeći se statističkim podacima iz razdoblja 2017. – 2024. i prognozama za 2025., primjenjuju se metode regresijske i indeksne analize za procjenu dinamike poreznih prihoda, BDP-a i poreznog opterećenja. Nalazi otkrivaju značajnu volatilnost fiskalnih pokazatelja u Ukrajini zbog rata, dok Hrvatska pokazuje postupan oporavak i stabilnost usklađenu sa standardima EU-a. Razvijeni indeks omogućuje usporedbu među zemljama i identificira prioritetna područja za reformu politike. Rezultati ističu da hrvatsko iskustvo nudi praktične uvide za poboljšanje fiskalne održivosti Ukrajine tijekom poslijeratnog oporavka
DOES INNOVATIVENESS MEDIATE THE RELATIONSHIP BETWEEN KNOWLEDGE SHARING AND COMPETITIVE ADVANTAGE?
No full textGlavni je cilj ovoga rada ispitivanje povezanosti između dijeljenja znanja i inovativnosti poduzeća te analiziranje njihove uloge u postizanju konkurentske prednosti poduzeća. Empirijsko istraživanje provedeno je na uzorku srednjih i velikih poduzeća koja posluju u Republici Hrvatskoj. Rezultati PLS-SEM analize potvrdili su da dijeljenje znanja ima pozitivan utjecaj na konkurentsku prednost poduzeća, kao i da potiče inovativnost poduzeća. Dokazano je i da inovativnost poduzeća posreduje u utjecaju dijeljenja znanja na konkurentsku prednost. Iz toga zaključujemo da dijeljenje znanja pozitivno utječe na konkurentsku prednost izravno, ali i neizravno na temelju utjecaja na inovativnost poduzeća.The main objective of this paper is to examine the relationship between knowledge sharing and business innovation and to analyse their role in achieving a competitive advantage for a company. This empirical study was conducted on a sample comprising medium and large companies in the Republic of Croatia. The results of the PLS-SEM analysis confirmed that knowledge sharing positively influences a company’s competitive advantage and fosters innovation. It has also been proven that a company's innovation mediates the effects of knowledge sharing on competitive advantage. From this we conclude that knowledge sharing positively influences competitive advantage directly, but also indirectly due to its impact on the company's innovation