Periodica Polytechnica (Budapest University of Technology and Economics)
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Current trends in library and information science in the light of PhD research and studies – 4.: Interview with Fredrick Wawire Otike
No full textThe editorial team of CELISR sent a questionnaire to recent graduates of the Library and Information Science doctoral program at the ELTE Doctoral School of Literary Studies, in order to provide the journal’s readers with an insight into the current and future scientific activities of researchers, and to give an idea of the current research trends in the field. The following article contains a brief overview of the PhD research conducted by Fredrick Wawire Otike, University Librarian at Dedan Kimathi University of Technology, Kenya, with background and future prospects.The editorial team of CELISR sent a questionnaire to recent graduates of the Library and Information Science doctoral program at the ELTE Doctoral School of Literary Studies, in order to provide the journal's readers with an insight into the current and future scientific activities of researchers, and to give an idea of the current research trends in the field. The following article contains a brief overview of the PhD research conducted by Fredrick Wawire Otike, University Librarian at Dedan Kimathi University of Technology, Kenya, with background and future prospects
Experimental and Numerical Investigation on the Effect of Finger Spread on Swimmer Performance
Full text linkThis study presents an experimental and numerical investigation on the effect of finger spread on the flow field around the swimmer's hand. Three hand models having different finger positions were analysed. The models were created by taking resin moulds of the hand of elite-level swimmer László Cseh. The models were digitised by high-resolution 3D scanning. Wind tunnel experiments were performed to measure the drag and lift forces acting on the hand. The measured data were also used to evaluate the performance of the CFD models in ANSYS Fluent. It was found that the magnitude of the drag force varied only slightly (by 1.65%) regarding the investigated cases; however, the maximum achievable lift increased significantly in the fully closed finger position. The difference in the measured maximum lift forces was ~67% between the fully open and fully closed finger positions. The numerical models underestimated the drag force but showed trends similar to the experimental results. The study highlights that while the finger spread influences the hydrodynamic forces acting on the swimmer's hand, the determination of an optimal finger spread requires further investigations considering the complete stroke trajectory. The presented methodology provides a solid foundation for future studies aimed to optimise swimmer performance and training
Manufacturing Process of Laboratory Bipolar Plates Designed with Gas Flow Simulation
Full text linkIn present paper a low-resource-demanding targeted manufacturing technique is demonstrated for serpentine-structured bipolar plates (BPPs) for Proton Exchange Membrane Fuel Cell (PEMFC) test systems. In the phase of the technical design, Computational Fluid Dynamics (CFD) simulations were conducted to analyze the BPPs during continuous operation. The simulations revealed that the proposed 4-serpentine flow field with channel and land width of 1 mm and channel depth of 2 mm effectively distributes reactant gases across the active area of the Membrane Electrode Assembly (MEA), minimizing stagnant flow regions under operating conditions. The CFD simulations demonstrated that the flow channel design facilitated efficient water drainage, reducing the risk of water accumulation that could impede gas diffusion and decrease cell performance. Water mole fraction at the outlet was calculated to 0.3, while power dissipation density of the active areas reached homogeneously 5.4 × 10−3 W/m3. BPPs with the appropriate structure were manufactured through a cost-efficient Wire Electrical Discharge Machining (WEDM) and Computer Numerical Control (CNC) milling technique highly appropriate for unique production of test cell components
Production and Testing of Syntactic Metal Foams Reinforced with Aluminium-silicon Partially Infiltrated Carbon Fibre Bundles
Full text linkSyntactic metal foams are porous materials with outstanding specific mechanical properties, such as high specific energy absorption and specific load-bearing capacity. However, due to the cellular structure, they are not suited for handling tensile loads. This study aims to create a composite structure in which carbon fibre bundles are embedded along the load direction in syntactic metal foams. The samples were produced by pressure infiltration of the fillers and the pre-infiltrated carbon fibre bundles. Tensile tests show that the fibre bundles increase the tensile load-bearing capacity of the specimens. The reference samples withstood 0.69 ± 0.07 kN tensile force. The reinforcement increased the density of the metal foam by 20% (from 1.21 ± 0.01 g∙cm−3 to 1.52 ± 0.01 g∙cm−3), while increasing the tensile load-bearing capacity to 1.80 ± 0.15 kN, an approximate increase of 260%, and 1.27 ± 0.10 kN an approximate increase of 180% in the case of 6 and 4 reinforcing carbon fibre bundles, respectively. The relationship between the load-bearing capacity (peak force) and the number of reinforcing carbon fibre bundles can be exactly described by a second-order polynomial function and can also be estimated by a simpler linear relationship
Best Practice Child- and Youth-friendly Cities: Development of an Integrated and Comprehensive Framework through a Systematic Review
Full text linkCreating a city that prioritizes the needs of children and youth is crucial for sustainable urban development. This paper reviews and explores best practices from international experiences excelling in Transportation Safety, Mobility, Accessibility, Sustainability, Climate Change, Inclusivity, 6 Es Approach, and Youth Empowerment and proposes an integrated and comprehensive framework for the establishment of the best practice child- and youth-friendly cities that would contribute to enhancing the safety of young people. The practices were assessed using predefined evaluation criteria to identify gaps, and then the elements and the requirements of the integrated and comprehensive framework were determined to bridge the identified gaps. An intensive review of 13 practices revealed that most studies (10 out of 13) fully considered Inclusivity and partly considered the 6 Es Approach criteria. However, the least considered criteria were Transportation Safety, Mobility, Climate change and Youth Empowerment. Interestingly, among all studies, only one considered Climate Change. The study concludes that future studies should incorporate underrepresented areas to bridge gaps. It emphasizes that local governments should prioritize child- and youth-friendly initiatives, adhering to human and child rights principles and recognized standards like the UNICEF Local Governance Approach. The study also highlights the importance of fostering meaningful participation from youth and children, focusing on capacity building, and committing to non-discrimination. Finally, it calls for clear roles and responsibilities for local governments, partnerships with public and private sectors, and regular monitoring and assessment to ensure the sustainability and success of these initiatives
Az erdélyi múlt digitalizálása: kihívások és sikerek
No full textDigitéka was launched at the end of 2018, initiated and operated by the School Foundation in Cluj-Napoca/Kolozsvár. It provides free access to digitized press materials, books, and databases in Hungarian from Transylvania, and its goal is to make the entire Transylvanian Hungarian press collection fully accessible. Initially, it expanded its content in cooperation with Arcanum and the Transylvanian Databank, but since 2022 it has been developing through its own scanning equipment and by striking an agreement with the Central University Library of Cluj. The platform contains not only its own digitized materials but also provides access to other Transylvanian digitized content through hyperlinks, functioning as a collecting library. By 2025, it has automated the workflow partly with the help of artificial intelligence, significantly accelerating content processing. It has built up a capacity to digitize approximately 250,000 pages per year. The website has 300-500 returning, and 2-3,000 one-time users per month, primarily from Romania and Hungary.Az Erdélyi Digitális Tudománytár (Digitéka)1 2018 végén indult, a kolozsvári Iskola Alapítvány kezdeményezte és működteti azzal a céllal, hogy teljeskörűen elérhetővé tegye az erdélyi magyar sajtóállományt. Közszolgálatot betöltve erdélyi magyar nyelvű digitalizált sajtótermékeket, könyveket és adatbázisokat tesz ingyenesen elérhetővé. Tartalmát kezdetben az Arcanummal és az Erdélyi Magyar Adatbankkal együttműködésben gyarapította, 2022-től viszont már saját szkennelő berendezés használatával és a Kolozsvári Központi Egyetemi Könyvtárral2 kötött megállapodás keretében fejleszti. A platform a saját digitalizált anyagok mellett hiperhivatkozásokkal más erdélyi digitalizált tartalmakhoz is hozzáférést biztosít, gyűjtőkönyvtári jelleggel. Működtetői 2025-re részben mesterséges intelligencia segítségével automatizálták a munkafolyamatot, jelentősen felgyorsítva a tartalomfeldolgozást, és évi mintegy 250 ezer oldal digitalizálására építették ki a kapacitást, a honlapon jelenleg 1 701 403 oldal digitalizált sajtó és könyv érhető el. A honlapnak havi 300-500 visszatérő és 2000-3000 egyszeri felhasználója van, legtöbben Romániából és Magyarországról
Külföldi könyvtár- és információtudományi folyóiratokból (referátumok)
No full text- Hubay Miklós: Referenszontológia alkalmazása a szemantikai interoperabilitás előmozdítására
- Kalcsó Gyula: A generatív mesterséges intelligencia és az információkeresés
- Bubnó Katalin: Relevancia nélküli discovery rétegek? Három közismert könyvtári keresőeszköz vizsgálata és bizonyítékokon alapuló értékelése
- Kalcsó Gyula: Az adatlekéréssel kiegészített generálás (RAG) integrálása az akadémiai könyvtári kereső- és lekérdezőrendszerekbe
- Szőnyegi Zsanett: Generatív mesterséges intelligencia egyetemisták számára: közösen fejlesztett online tananyag a generatív MI-ről az egyetemi képzésben
- Rényi Mátyás: Egy digitális megőrzési (pilot) program indítása
- Kalcsó Gyula: Webarhívumok metaadatainak automatikus generálása a GPT-4o generatív nyelvi modellel
