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ANALYSIS OF THE RELATIONSHIP BETWEEN OWNERSHIP STRUCTURE AND THE QUALITY OF CORPORATE GOVERNANCE
No full textRad analizira povezanost vlasničke strukture i kvalitete korporativnog upravljanja u hrvatskim dioničkim društvima uvrštenima na Zagrebačku burzu. Svrha istraživanja jest utvrditi u kojoj mjeri koncentracija vlasništva i tip većinskog vlasnika utječu na razinu usklađenosti s Kodeksom korporativnog upravljanja te na pokazatelje učinkovitosti poslovanja. Empirijska analiza provedena je na uzorku od 30 društava korištenjem podataka iz godišnjih izvješća, financijskih pokazatelja i izvješća o korporativnom upravljanju za 2024. godinu. Primijenjene su metode deskriptivne statistike, korelacijske analize i t-testa. Rezultati pokazuju da je vlasništvo u promatranim društvima visoko koncentrirano, no koncentracija nije statistički značajno povezana s razinom formalne usklađenosti s Kodeksom. Istodobno, broj neovisnih članova nadzornih odbora pokazuje negativnu povezanost s pokazateljem povrata na kapital (ROE), dok tip vlasnika pokazuje ograničen, ali vidljiv utjecaj na praksu upravljanja. Doprinos rada očituje se u empirijskoj potvrdi suvremenih teorijskih spoznaja o ulozi vlasništva u oblikovanju kvalitete upravljanja na tržištu u razvoju poput hrvatskog.The paper analyses the relationship between ownership structure and the quality of corporate governance in Croatian joint-stock companies listed on the Zagreb Stock Exchange. The purpose of the research is to determine the extent to which ownership concentration and the type of majority owner influence the level of compliance with the Corporate Governance Code and business performance indicators. The empirical analysis was conducted on a sample of 30 companies using data from annual reports, financial indicators, and corporate governance statements for the year 2024. Descriptive statistics, correlation analysis, and t-tests were applied. The results show that ownership in the observed companies is highly concentrated, although concentration is not statistically significantly related to the level of formal compliance with the Code. At the same time, the number of independent supervisory board members is negatively associated with return on equity (ROE), while the type of owner has a limited but noticeable influence on governance practices. The paper contributes by empirically confirming contemporary theoretical insights into the role of ownership in shaping governance quality in developing markets such as Croatia
Multi-Criteria Data Analysis of China-Europe Railway Express – An Integrated Network Approach
No full textThis study introduces an innovative, integrated approach to analyse the China-Europe Railway Express (CRE) network, combining the entropy weight method, improved gravitational model and social network analysis. These methodologies can provide a comprehensive comparison and reveal structural differences between Chinese and European railway segments. Through quantifying logistics industry development levels, inter-city connection intensities and network centrality, the study provides insights into the CRE network’s operational dynamics. Key findings include the identification of critical nodes, cohesive subgroups and contrasting network structures between China (centralised) and Europe (decentralised). The improved gravitational model, incorporating GDP proportions for asymmetrical attractions and time distance measurements, represents significant advancements in spatial interaction analysis for logistics networks. The study proposes prioritising electrified rail sections between high-attraction pairs (Chongqing-Duisburg) and adopting solar-powered terminals at hubs like Wuhan and Duisburg for sustainable networks. It is well anticipated that the methods, models and research findings from this study will contribute to network optimisation, policy formulation and sustainable development of international logistics systems, particularly within the context of the Belt and Road Initiative, which is of rising significance for Eurasia geopolitical and cross-continental economic cooperation
Assessing the Effects of Implementing Railway Technological Innovations on the Competencies of Logistics Specialists
No full textThe level of technological innovation and the efficiency of transport logistics in enterprises principally depend on the resources that are used. The authors aim to develop a new approach to assess the interface between railway innovation implementation and the competencies of logistics specialists. The application of advanced technologies, such as digitisation and automation, substantially improves key performance indicators while simultaneously lowering operational costs for railway undertakings. There are notable advancements in technology within railway transport, with a particular emphasis on digitalisation. Analysis and research to determine specific engineering competencies of logistics specialists are highly anticipated and needed. This research focuses on the analysis and assessment of the interconnection between technological innovations in railway transport and the engineering competencies of logistics specialists. An analytic hierarchy process (AHP) method is used to assess the impact of technological innovations on the engineering competencies of logistics specialists, aiming to establish the presumed link between social psychological and technological factors. A new approach for assessing the competencies of logistics specialists in the railway sector has been developed. It is proven that the implementation of technological innovations within railway companies serves as the decisive factor driving the improvement of engineering competencies for logistics specialists
Computer simulation use in sand casting process optimisation
No full textThe main aim of this paper was to determine the optimal design of a sand mould using computer simulation and statistical optimisation techniques. Simulations of the sand-casting process were performed using NovaFlow&Solid software. The geometry of the mould and the type of sand used were varied according to the Taguchi L18 design of experiments. Output variables used to assess process quality and efficiency were total casting time, volume shrinkage, and melt efficiency. Taguchi-based grey relational analysis was used to identify the optimal process parameters. The combination of input parameters represents the optimal solution for process simulation resulting in minimal total casting time, minimal volume shrinkage and maximum melt efficiency. The proposed methodology provides an effective framework for simplifying the casting process and enhancing the reliability of gravity-cast components
Numerical investigation of the hydrodynamic characteristics and interactions of an unmanned surface vehicle chasing a mother ship during recovery
Full text linkUnmanned surface vehicles (USVs) require efficient and reliable recovery at sea. However, the recovery process, involving USVs chasing a mother ship, is complex and risky due to wave-making and wake effects that impact USV stability and resistance. It is necessary to study the interaction between the USV and the mother ship during the docking process in order to understand the changes in the motion performance of the unmanned ship during docking and provide a basis for the subsequent optimization of the control method and recovery path of docking recovery. This study numerically simulates the hydrodynamic behaviors of a 175-USV developed by Huazhong University of Science and Technology chasing alongside a KRISO Container Ship (KCS) standard model during recovery. 175-USV lake tests and corresponding simulations were compared and analyzed, which show good accuracy. Simulations reveal time-varying hydrodynamic characteristics as the USV operates into calm water, in coming waves of varying amplitudes and directions. Findings show roll angles and moments fluctuate within the location range of 35-45 % of the mother ship length to the stern, with swaying force peaking near the location of 10 % of mother ship length to the stern due to suction effects. Waves increase motion responses and loads, especially under oblique wave conditions, yet smoother regions persist on the opposite side of incoming waves. This study reveals the interaction between the hydrodynamic properties and the ship during docking, which supports the safe and reliable recovery of unmanned vessels
Design of an adaptive PI speed controller for FOC-driven underwater thrusters
Full text linkUnderwater thrusters are the primary actuators in marine vehicles. The thruster drive and control methods for these thrusters considerably influence their dynamic response, accuracy, and efficiency. This study reviewed the structure of field-oriented control (FOC) and six-step commutation (SSC)–driven thrusters, comparing their advantages and disadvantages in underwater applications. Considering the dynamic performance of open-loop SSC, the precision of closed-loop SSC, and the energy efficiency of FOC, an adaptive proportional–integral (API) speed controller was introduced for FOC-driven underwater thrusters, which demonstrated superior performance in underwater conditions. Simulations were conducted to reveal the performance differences between FOC- and SSC-driven underwater thrusters and the advantages of the designed API controller in FOC-driven systems. FOC with a conventional PI speed controller exhibited a chattering-free steady state and 22.9% higher energy efficiency than the closed-loop SSC, and the API-based FOC showed improved step signal response and a 25.9% increase in amplitude bandwidth compared with conventional PI and integral–separated PI control. Furthermore, the API controller avoided speed chattering at low speed and displayed lower steady-state error than the conventional PI controller. These results support the conclusions of the higher bandwidth and overshoot avoidance of API and the higher energy efficiency of the FOC-driven motor
Tree Crown Defoliation Degree as a Predictor of Silver Fir (Abies alba Mill) and Norway Spruce (Picea abies (L.) Karst.) Timber Value
Full text linkNorway spruce (Picea abies (L.) Karst.) and silver fir (Abies alba Mill.) are both economically and ecologically important coniferous tree species in Europe. Due to climate change, both of them are affected by dieback. This paper examines the quantity, quality, and value of roundwood produced from healthy, severely defoliated (61–99%) and dead Norway spruce and silver fir trees. The study was conducted in four subcompartments located in the Forest Administration Delnice, Management Unit »Milanov vrh«. In total, 81 trees of silver fir (208.77 m3 of gross volume) and 83 trees of Norway spruce (208.43 m3 of gross volume) were measured. Study results showed that the measured gross volume of silver fir was by 8.29% higher than predicted by the harvesting plan, while the measured gross volume of Norway spruce was slightly higher by 0.90%. The determined assortment structure showed a negative correlation between tree crown defoliation degree and the share of highly valuable assortments for both researched species. Healthy trees of silver fir had the highest share of veneer logs, while dead silver fir trees had the highest share of pulpwood. Silver fir dead trees also had the highest share of waste (22.19%), while healthy and severely defoliated trees had 18.69% and 18.47%, respectively. In the case of Norway spruce, healthy trees had the highest share of veneer logs, while dead trees had the highest share of pulp wood. At the same time, the share of waste remains almost the same regardless of the tree crown defoliation degree (from 17.97% for dead trees to 18.17% for healthy trees). Results of the determined assortment structure reflected on the average tree value, which was also negatively impacted by the tree crown defoliation degree. In the case of silver fir, the value of dead trees along DBH classes was 25.6% to 41.6% lower than for healthy trees, while in the case of Norway spruce, the value of dead trees was 22.4% to 36.3% lower than that of healthy trees. The initial hypothesis that average tree value decreases in the order: healthy trees > severely defoliated trees > dead trees was confirmed. To improve harvesting plans, the inclusion of a tree crown defoliation degree as an additional predictor of assortment structure is strongly supported by the results of this study
