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Design and Analysis of a Novel Non-isolated DC-DC MMC Architecture for HVDC Power Networks Interconnections
No full textHigh voltage direct current (HVDC) power structures provide various notable advantages over high voltage alternating current (HVAC) power grid structures, including superior efficiency, faraway and large-scale transmission power, flexibility, controllability, minimal operating costs with positive effects on the environment, interconnection of asynchronous power systems. As HVDC systems are implemented, the demand for advanced DC-DC converters to facilitate voltage-level adaptations in interconnected networks has grown. The DC-DC Modular Multi-level Converters (MMCs) are a tremendously practical and cost-effective converter architecture appealing for interconnecting HVDC power systems. This study presents a unique DC-DC MMC architecture that provides an excellent solution for integrating modern asynchronous HVDC networks and these modern HVDC power systems with existing HVAC power systems. The suggested innovative DC-DC MMC has numerous advantages, including lower volume, more appealing funding cost, and less SMs quantity. The transformerless approach significantly reduces the converter's volume, weight, price, and power loss. To precisely control the power transfer among power systems with varying or comparable voltage levels, this unique study presents a power transfer control system. The performance of the proposed system is validated through mathematical modelling, harmonic analysis, and simulations, demonstrating its capability to effectively interconnect HVDC power systems
Umjetna inteligencija, igrifikacija i održivi razvoj: uloga školskih knjižničara u novom obrazovnom okruženju
No full textRad istražuje mogućnosti integracije umjetne inteligencije (UI) i igrifi kacije u obrazovanju, s naglaskom na njihov doprinos održivom razvoju i ulogu školskih knjižničara u novoj obrazovnoj paradigmi. Analizira se kako UI alati mogu personalizirati učenje, pratiti obrazovni napredak i doprinijeti stvaranju pravednog i uključivog obrazovnog okruženja. Igrifikacija se razmatra kao strategija za povećanje motivacije i angažmana učenika, osobito u kontekstu poučavanja o ciljevima održivog razvoja. U središtu rada je uloga školskih knjižničara koji, osim što upravljaju
informacijskim resursima, sudjeluju u razvoju digitalne i podatkovne pismenosti te promiču etičku i odgovornu upotrebu tehnologije. Primjerima dobre prakse i relevantnim izvorima, pojašnjavaju se ključni koncepti povezani s etikom UI sustava, poput algoritamske pristranosti, digitalne pravednosti i personalizacije obrazovanja. Zaključno, ističe se kako sinergija umjetne inteligencije, igrifi kacije i stručne podrške školskih knjižničara može doprinijeti razvoju inovativnog, održivog i učeniku usmjerenog obrazovnog sustava
A Scalable Distributed Approach for Exploration Global Frequent Patterns
No full textFinding patterns in transactional databases regularly is an essential part of data mining since it makes it simpler to identify significant connections and reoccurring patterns in datasets. Scalable, high-performance computing solutions that employ parallel computing systems to optimize resource efficiency and data analysis as data volumes continue to grow are necessary for efficiently processing large databases. To solve these issues, this paper presents Exploration Global Frequent Patterns (EGFP), a new parallel algorithm designed to generate global frequent patterns in different distributed datasets. By facilitating the distribution of workloads and data partitioning, the approach reduces communication costs and ensures efficient parallel execution. Our approach uses two prefix-tree structures to generate a significantly compacted and structured representation of frequent patterns. The first structure local-tree serves to store local support values to effectively collect and arrange transaction data. Global prefix counts are then aggregated and ranked to improve frequency-based analysis and provide a more organized and useful representation of frequent patterns. To find the globally prevalent patterns, a Master site develops a second structure global-tree for each prefix based on this arranged data. Experimental results on large-scale benchmark datasets show that EGFP outperforms other existing methods including CD and PFP-tree in terms of execution time and scalability, while incurring considerably less communication cost
An Improved Energy Management Strategy for Hybrid Power Systems using Dual Predator Optimization
No full textIn this research work, the proposed Dual Predator Optimization algorithm is inspired by the hybridization of the very well-known Whale Optimization Algorithm and Grey Wolf Optimization. This algorithm integrates with a hybrid micro-grid to optimize the use of renewable resources, reduce reliance on fossil fuel, and increase the cost-effectiveness of using excess energy by adjusting these parameters over time. The Dual Predator Optimization is flexible and more suitable for hybrid energy management. The findings indicate that Dual Predator Optimization effectively manages hybrid systems by substantially lowering electricity expenses and diminishing the likelihood of supply interruptions. It was determined that in comparison to the hybridization algorithms, the Cost of Energy of the proposed Dual Predator Optimization technique is reduced to an average of 20%, however, the Loss of Power Supply Probability rises to an average of 7.5%. it offers zero load shedding within the hybrid system with 100% renewable-satisfied energy production for the microgrid. Moreover, the proposed Dual Predator Optimization outperformed others in terms of producing hydrogen by 21.10% and 17.60% respectively. The findings indicate that Dual Predator Optimization is a superior method for addressing energy reliability and environmental sustainability issues
Implementation of Knowledge-based Management System for Enterprises Key Carbon Neutral Measures by Grey Relational Analysis
No full textThis study uses Grey Relational Analysis to investigate corporate resource allocation strategies for carbon reduction. Analysing 214 valid survey responses, it identifies five key measures prioritised by companies: "Resource recovery and reuse" as the most critical, followed by "Energy-saving lighting and equipment." "Enhancement of energy-saving behaviours" and "Optimisation of energy efficiency" are also important, with "Energy-saving policies and management" providing essential support. The research offers a novel perspective on resource allocation strategies and proposes a dynamic knowledge management system framework to evaluate and improve carbon reduction initiatives. Managerial implications include prioritising resource allocation, enhancing employee training, investing in advanced technologies, and reinforcing policy-making support. Recommendations for designing questionnaires tailored to information systems are provided, along with a system interface example to help businesses track carbon reduction progress
Promotion of teachers to higher ranks from the perspective of expert teachers
No full textEkspertnost u području pedagogije znatnije se počela istraživati krajem prošlog i početkom ovog stoljeća, a uočeno je da učitelji eksperti posjeduju niz karakteristika koje odgojno obrazovnu djelatnost čine kvalitetnijom. Fleksibilnost, analitičnost, dobro razumijevanje apstraktnih ideja, osjetljivost na detalje, bolje strategije rješavanja problema i donošenja odluka neke su od karakteristika učitelja eksperata. Kontinuiranim radom na vlastitom profesionalnom razvoju učitelji postižu izvrsnost u svom području rada i postaju eksperti, a svoju ekspertnost, među ostalim, pokazuju i napredovanjem u zvanje. Cilj ovog istraživanja bio je ispitati iskustva učitelja eksperata o napredovanju u zvanje i njihovoj ulozi unutar odgojno obrazovnog sustava. Primijenjeno je kvalitativno istraživanje provedbom fokus grupe. Podaci su prikupljeni polustrukturiranim intervjuom s osam učiteljica koje su stekle zvanje učiteljice savjetnice ili izvrsne savjetnice. Dobiveni rezultati ukazuju da postoje brojni izazovi u napredovanju učitelja u zvanja te da su učitelji eksperti često neiskorišteni potencijal u odgojno-obrazovnom sustavu.Expertise in the field of pedagogy began to be more thoroughly researched at the end of the last and the beginning of this century. It has been observed that expert teachers possess a range of characteristics that enhance the quality of educational system. Flexibility, analytical thinking, a strong understanding of abstract concepts, attention to detail, and better problem solving and decision-making strategies are among the traits of expert teachers. Through continuous work on their own professional development, teachers achieve excellence in their field and become experts, demonstrating their expertise, among other ways, through advancement to higher professional ranks. The aim of this research was to explore the experiences of expert teachers regarding professional advancement and their role within the educational system. A qualitative study was conducted using a focus group. Data were collected through semi-structured interviews with eight female teachers who had attained the titles of teacher advisor or teacher excellent advisor. The findings indicate that there are numerous challenges in the process of professional advancement into higher ranks for teachers and that expert teachers often represent an underutilized potential within the educational system
