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Safety Management at Tower Crane in Construction Site
No full textTower cranes are critical in high-rise construction but present significant safety risks due to their structural characteristics and operational complexity. This study analyzed 73 serious tower crane accident cases reported to the Korea Occupational Safety and Health Agency between July 2012 and July 2020. A mixed-methods approach was applied, combining quantitative accident data analysis with surveys and expert interviews. Statistical proportions were calculated to identify high-risk factors. Lifting operations accounted for the highest proportion of accidents (45.3%), with falls being the most common disaster type (35.8%). The leading cause of accidents was non-compliance with safe work procedures (38.8%). Survey and interview findings highlighted insufficient training, lack of standardized signal protocols, and limited on-site safety supervision. Strengthening training programs, standardizing signal operations, and enforcing systematic safety management can significantly reduce tower crane accidents. Policy recommendations and a framework for continuous monitoring are proposed
Real-Time Hybrid Query Transformation Method for Enhancing Search System Performance in Korean Language Applications
No full textThis study addresses the real-time performance limits of Korean-language search systems caused by morphological complexity and the cost of semantic processing. We propose a hybrid query transformation method that couples rule-based preprocessing with a Transformer-based postprocessor. The rule-based stage simplifies agglutinative input, and the Transformer refines user intent and semantic context. On a curated Korean query set, our approach attains 89.0% Precision@5 (95% CI: 87.2–90.7) with 95 ms average latency (95% CI: 92–98), about 21% faster than an NLP-only baseline. User surveys and expert interviews further confirm practical applicability. To strengthen reliability and scope transparency, we report five-fold cross-validation, noise-robustness tests (spacing errors, minor typos), and comparisons against open proxy baselines (e.g., BM25+ KoNLPy). These additions clarify the study’s focus on Korean while providing reproducible evidence of robustness, positioning the framework as deployment-ready for Korean and a solid basis for future multilingual extensions
User Experience in Mobile Language Learning Applications (MLLA): Insight from Mixed-Methods Triangulation Study
No full textMobile Language Learning Applications (MLLAs) are gaining widespread use in higher education because of the flexible nature of practice opportunities with languages. The majority have easy-to-use interfaces, but few enable long-term engagement, retention, and productive learning. There is much empirical work that isolates usability or outcomes singularly without noting how user experience, motivation, and pedagogy intersect in the mobile environment. This study investigates MLLA user experience among university students in Indonesia using a mixed-methods design. Structural Equation Modelling (SEM) was used to investigate the inter-plays of usability, acceptance, engagement, and retention. Qualitative data provided information about user views and context-based limitations. Findings suggest that while overall MLLAs are usable and widely accepted, they tend to lack instructional intensity and intrinsic motivation support. Motivation and perceived usefulness significantly impact engagement, but redundant repetition, superficial individualization, and minimal interaction reduce retention. With reference to TPACK, FRAME, and SDT, the study highlights learner-centered design featuring effective pedagogy, social interaction, and adaptive functionality as being vital. To transcend surface gamification, MLLAs must support deep, long-term language learning. These results provide actionable recommendations for developers and instructors seeking to optimize mobile language learning by synergizing technology, pedagogy, and learner psychology
Influence of inevitable hydrogen evolution reaction on morphology of electrodeposited zinc
No full textInfluence of parallel hydrogen evolution reaction (HER) on morphology of zinc electrodeposits has been investigated. Zn was electrodeposited potentiostatically from the alkaline electrolyte at overpotentials both inside and outside the plateau of the limiting diffusion current density, and scanning electron microscopy (SEM) was used to characterize the resulting deposits. Holes originating from detached hydrogen bubbles were formed among the branchy, fern-like dendrites at overpotentials outside the plateau of the limiting diffusion current density, while HER was not detected at the overpotential inside the plateau. The overpotential of electrodeposition had no significant effect on the amount of hydrogen produced (the HER current efficiency was in the 17.7-19.1 % range), but it did affect the hole size. Depending on the overpotential of the electrodeposition, the size of holes was from several to about 100 mm, including those obtained by a coalescence of neighbouring hydrogen bubbles, and decreased with the increasing overpotential. The absence of inhibition of dendritic growth in spite of a high value of evolved hydrogen was attributed to Zn, which belongs to the group of normal metals characterized by high values of both the exchange current density and the overpotential for hydrogen evolution
PREMA ODRŽIVOM FINANCIRANJU: UNAPREĐENJE STUDIJSKIH PROGRAMA EKONOMSKIH FAKULTETA U HRVATSKOJ
No full textThe study investigated the extent to which sustainable development and finance are embedded in teaching and research activities and examined the attitudes of finance teachers and the perceived institutional support for improving sustainability education in economics faculties and departments of universities in Croatia. The results of the survey were analyzed using descriptive statistics, categorical frequency analyses, Mann-Whitney test, t-test and correlations: Non-parametric Spearman correlation and parametric Pearson product moment correlation. The research findings confirm the importance of human capital - the role of teachers in implementing and enforcing the concept of sustainable finance/development. The effective implementation of the concept of sustainable finance in the teaching process is linked to an institutionally clear concept of sustainable development, scientific work and study abroad. The introduction of sustainable finance courses is more present at the graduate level than at the undergraduate level, where sustainable finance topics are gradually introduced into existing courses.Ovaj rad istražuje u kojoj su mjeri održivi razvoj i financije ugrađeni u nastavne i istraživačke aktivnosti te ispituje stavove nastavnika financija i percipiranu institucionalnu podršku za poboljšanje obrazovanja o održivosti na ekonomskim fakultetima i odjelima sveučilišta u Hrvatskoj. Rezultati ankete analizirani su korištenjem deskriptivnom statistikom, kategorijalnom frekvencijskom analizom Mann-Whitneyeva testa, t-testa i korelacija: neparametrijskom Spearmanovom korelacijom i parametrijskom Pearsonovom produkt moment-korelacijom. Nalazi istraživanja potvrđuju važnost ljudskog kapitala, odnosno ulogu nastavnika u primjeni i provođenju koncepta održivih financija/razvoja. Učinkovita primjena koncepta održivih financija u nastavni proces povezana je s institucionalno jasnim konceptom održivog razvoja, znanstvenim radom i studiranjem u inozemstvu. Uvođenje kolegija održivih financija više je prisutno na diplomskoj nego na preddiplomskoj razini, gdje se teme održivih financija postupno uvode u postojeće kolegije
The Impact of Spatio-Temporal Constraints on Tourists’ Travel Mode Choice Behaviour – Case of Sijiao Island, China
No full textWith the continuous rise in tourism consumption demand, the spatio-temporal aggregation effects are strengthening, leading to an imbalance in travel structure within tourist destinations. To address these issues, this study focuses on SiJiao Island in Zhoushan, China. It empirically studies tourists’ mode choice behaviour from the perspectives of personal social attributes, temporal attributes and spatial attributes. This study gathers tourist characteristics through surveys and multidimensional data mining. It employs a multinomial logistic regression method to identify influencing factors and constructs a gradient boosting decision tree model to explore the relationship between spatio-temporal factors and tourists’ mode choice behaviour. The results show that the cumulative importance of temporal and spatial attributes is much greater than that of personal social attributes. Among the many spatiotemporal influencing factors, travel distance, transfer time, departure time and the number of bus stops have a significant impact on tourists’ mode choice behaviour, accounting for 26.25%, 16.57%, 14.65% and 11.87% of the total importance, respectively. Additionally, there are complex non-linear relationships between these influencing factors and tourists’ mode choice behaviour. The interaction effects of spatiotemporal combinations on tourists’ mode choice behaviour exhibit correlations. The sensitivity of mode choice to different spatiotemporal factors varies
Modelling and Trajectory Tracking Control of Multi Differential Wheel Heavy-Duty AGV Based on Koopman Operator
No full textAutomated guided vehicles (AGVs) are extensively applied in aerospace, ports, docks, rail transit, and other industries that require intelligent handling of heavy loads. Accurate modelling and trajectory tracking are crucial for performing the intelligent transfer of large objects and components using AGVs. To address the insufficient precision of current mathematical models and their inability to precisely perform trajectory tracking tasks due to the nonlinearity and strong coupling of multi differential wheel heavy-duty AGVs, a trajectory tracking control strategy based on the Koopman operator is proposed in this paper. First, based on the Koopman operator, an approximate high-dimensional linear dynamic explicit expression for the multi differential wheel heavy-duty AGV system is obtained using extended dynamic mode decomposition. Then, based on the obtained expression, a linear model predictive controller (MPC) is designed to achieve trajectory tracking control for heavy-duty AGVs. Finally, through simulation and experimental verification, it is demonstrated that the model information obtained from the data is effective and fits the dynamic model of the multi differential wheel heavy-duty AGV well. Comparisons reveal that its model accuracy is higher than that of the traditional Lagrange model; the root mean squared error (RMSE) and relative RMSE based on the Koopman model increase by an average of 24.86% and 3.24%, respectively. The designed linear model based on the Koopman operator can be combined with model predictive control. The controller can effectively perform trajectory tracking control, verifying its effectiveness. This work is the first experimental verification of the Koopman operator in heavy-duty AGV control, which will promote the engineering application of complex nonlinear systems
Tonći Kokić, Osnove filozofije znanosti. Split: Filozofski fakultet Sveučilišta u Splitu, 2024.
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