Periodica Polytechnica (Budapest University of Technology and Economics)
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Enhancing Decision-making in Uncertain Domains through Optimized Fuzzy Logic Systems
Get PDFFuzzy logic helps manage human-like reasoning in system control, mainly when traditional analysis does not work due to complex control processes. Despite its usefulness, fuzzy logic faces challenges in decision-making, especially in complex business situations and when combined with expert systems. It struggles with uncertainty and relies on various beliefs and assumptions, which is limiting compared to other methods for handling uncertainty. However, fuzzy logic can improve traditional control systems by adding a layer of intelligence. This study adapts mathematical functions like the straight-line point-slope equation, the absolute value function, and the Gaussian equation to develop accurate and flexible membership functions for fuzzy logic systems. By analyzing 10,000 tasks of different sizes, we found our methods significantly more precise than traditional approaches, especially in determining degrees of membership for uncertain and complex environments. Our MATLAB research shows the potential of using varied membership functions to enhance fuzzy logic systems' accuracy and flexibility
Towards Sustainable Transport: An Analysis of Urban Mobility in Hyderabad, Telangana Using Uber Movement Data
Get PDFCities worldwide face traffic congestion, challenging sustainable development and requiring insight into its dynamics, dispersion, and stability. Effective traffic management is pivotal for fostering sustainable urban mobility and enhancing quality of life. Leveraging Uber movement data, this study examines travel times and speeds across Hyderabad over a four-year span from 2016 to 2019. Congestion and friction indices from travel time matrices, along with network analysis, gauge urban accessibility, revealing similar magnitudes of Congestion and Travel Time Delay Transition Indices for inbound and outbound traffic within specific intervals. Notably, there is an inverse proportional relationship between these two indices. The Congestion Index values indicate that most zones experience significant traffic jams, while the Travel Time Delay Transition Index was calculated to affirm its inverse relationship with the Congestion Index. Employing fractal geometry, the study delves into the spatial complexity of the network and its correlation with urban growth parameters, contributing to sustainable urban planning efforts. Furthermore, the fractal dimension value obtained from the Mass-Radius method is 1.6955, with a correlation coefficient of 0.99, indicating a high degree of linearity between the road network and friction index. Results underscore the intricate interplay between traffic congestion, macroeconomic factors, and urban form, highlighting the imperative of integrating sustainability principles into transportation policies. By leveraging readily available Uber movement data, this research provides a comprehensive assessment of citywide traffic conditions, offering valuable insights for crafting sustainable transportation management strategies aimed at mitigating congestion and promoting equitable access to mobility
Development and Physicochemical Analysis of SrO/Hydroxyapatite Modified Mineral Trioxide Aggregate Synthesized from Calcium Carbonate and Tetraetyl Ortosilicate as an Endodontic Material
Get PDFMineral trioxide aggregate (MTA) is utilized in endodontics for root fracture repair, apexification, and as a root canal filling material. MTA possesses favorable sealing capability and biocompatibility. However, its clinical performance is limited by low mechanical performance at the early stage of hydration. In the present study, the limitations of MTA were addressed by incorporating SrO and hydroxyapatite (HA) into its formulation. MTA was synthesized using calcium carbonate as the calcium oxide precursor and tetraethyl orthosilicate as the silica source. The synthesis employed a sol–gel method followed by a solid-state calcination process at 1000 °C. The hydration of material was performed with water at a powder-to-liquid ratio of 3:1 (w/v). The study found that incorporation of 5% SrO into MTA enhanced the formation of calcium silicate hydrate (C–S–H) phases, as evidenced by increased X-ray diffraction peak intensity at 2θ = 29.3°. This modification also increased the compressive strength after seven days of hydration, sustaining an alkaline pH environment. MTA composite containing 5% SrO combined with 6% HA further amplified the intensity of C–S–H formation. Morphological analysis showed that the development of hydration reaction reduced porosity and voids, yielding a more regular microstructure. An increase in HA concentration leads to a decrease in the pH of the material, trending toward neutrality by days 7 and 28. Such pH modulation can reduce the localized acidity and thereby minimize inflammatory responses when the material is applied in biological settings
Sustainable Utilization of Red Mud and Glass Waste in Alkali-Activated Cements: Design and Performance of Products
Get PDFRed mud (RM) is a hazardous waste that is generated in large quantities, and its sustainable, rational treatment and recovery is still a challenge. The aim of this research is to develop higher added value alkali-activated cements (AACs), which, by using red mud, can help to protect limited resources, reduce pollution, and produce alternative, "greener" building materials. During this work, industrial waste materials – blast furnace slag, red mud, and glass waste – were used to produce AACs suitable for traditional construction applications (e.g., load-bearing structures, foundation blocks, and walkways). Key parameters including the maximum RM content (recommended 21.7 wt% to maintain sufficient strength), composition of the activating solution, liquid/solid ratio, particle size, and reactivity of the glass waste were optimized. Glass waste reactivity was enhanced by high-energy grinding at 200 rpm for 90 minutes, resulting in a maximum compressive strength of 66.8 MPa, exceeding the highest strength class defined by relevant standards (EN 197-1). Mechanical properties were supported by microstructural analyses (SEM, FT-IR), and heavy metal behavior was assessed through leachate and adsorption tests. The AACs effectively immobilized heavy metals such as Cd, Ni, Pb, and Hg, with long-term leaching resistance and improved retention capacity compared to Portland cement-based mortars. Additionally, powder-based Pb2+ adsorption tests confirmed that RM-containing AACs offer enhanced performance in removing lead from aqueous solutions. Overall, these binders – containing up to 71.4 wt% combined industrial waste – demonstrate competitive mechanical and environmental properties, contributing to sustainable construction practices and potential wastewater treatment applications
Advanced Hybrid AI Models for Predicting Softening Point and Penetration of Modified Bitumen
Get PDFEnsuring bitumen quality is essential for the durability of asphalt pavements. Conventional laboratory tests for softening point (SP) and penetration (P) are reliable but labor-intensive and time-consuming, particularly for modified binders incorporating recycled additives. This study proposes an advanced hybrid machine learning (ML) framework integrating Neural Architecture Search (NAS) with Artificial Neural Networks (ANN) to predict the SP and P of modified bitumen containing crumb rubber (CR), coffee grounds (CG), and olive pomace (OP). A dataset of 49 laboratory-prepared samples was used to train and validate three models – Random Forest (RF), ANN, and NAS-ANN – evaluated through statistical indicators (MSE, RMSE, R2, R). The NAS-ANN achieved the best performance, with R = 0.9665/0.9567 for SP and 0.9726/0.8711 for P (training/validation). Sensitivity analysis indicated that OP had the most significant influence on SP, followed by CR and CG. The optimized NAS-ANN model was implemented in a user-friendly interface named SmartBit-AI, designed to facilitate rapid prediction and mix-design preselection. Overall, the proposed NAS-ANN framework complements conventional laboratory testing, offering a practical and efficient tool for accelerating sustainable bitumen evaluation and design
Investigation and Analysis of Electrical Faults in the Seven-phase Induction Machine
Get PDFMultiphase induction machines have revolutionized the propulsion and traction sector, thanks to their fault tolerance. This paper is focused on the analysis of electrical faults in the squirrel cage Seven-Phase Induction Machine (SPIM). This study provides a solid basis for diagnosing various faults by analyzing their distinct signatures for the electric faults that can affect this machine. To this end, a transient finite element model is elaborated to study these several electrical faults in SPIM. This paper will be devoted to the study of opening faults in various stator phases (one phase, two adjacent phases, two non-adjacent phases and two far phases), and shortcircuiting between turns of stator phases (5%, 10%, 15% of the first phase). An analysis of electromagnetic torque ripple, joule loss and efficiency is undertaken in this paper
A Review of the Necessity of Improved Life Cycle Inventory Data Quality in Evaluating Renewable Fuels Supported by a Case Study of Recycled Carbon Fuels
Get PDFClimate change is the most significant environmental challenge facing the world today. The EU is implementing various strategies to create a legislative and proposal framework for its Member States, promoting environmental sustainability through the European Green Deal. The EU aims to make Europe the first climate-neutral continent, requiring significant reductions in greenhouse gas (GHG) emissions from the energy sector, including initiatives under the Clean Energy Transition prioritizing renewable fuels. Besides weather-dependent renewables – aligned with waste management regulations – waste-based fuels like recycled carbon fuels (RCFs) can also aid the transition when the 70% GHG emission saving criterion is fulfilled, which is highly dependent on the accuracy of the input data. Digitalization will help higher renewable energy integration, but the extensive use of data requires preserving high privacy, safety, and security standards. Systematic literature research identified blockchain-based systems as an appropriate choice for advanced data collection. Data from a Hungarian municipal solid waste sorting facility was used to investigate the effect of data accuracy on GHG emission saving results of a RCF, comparing the EU regulated calculation method and the holistic life cycle assessment (LCA) method suitable for analyzing complex systems, complemented with a sensitivity analysis. Results showed that the GHG emission saving increases by 4.5 percent points using LCA compared to the EU regulated method. The sensitivity analysis proved the necessity of accurate data as a 1% change of input parameters resulted in a maximum two-fold relative change in GHG emission savings
Assessment of Trans Banyumas Services Based on the Opinions of Female Passengers from a Promotional Point of View
Get PDFPublic transportation is a fundamental element significantly influencing smart cities and smart mobility within communities. Banyumas Regency is currently one of the regions implementing the smart city concept in its urban development. One of the tangible proofs of this implementation by the Banyumas Regency government is the introduction of BRT Trans Banyumas, aimed at increasing public interest in using public transportation, facilitating more effortless mobility, reducing air pollution, and boosting the local economy. Evaluating public transportation services is essential to attract public interest, particularly regarding the intelligent public transport system (IPTS) aspects. This study evaluates Trans Banyumas services to analyze the level of IPTS implementation from the perspective of female passengers. Female passengers′ perceptions are used because women have unique mobility patterns, making them an essential indicator for assessing smart mobility. The method used in this research is General Linear Model ANOVA. Data collection was conducted qualitatively with 357 respondents. The test results show that demographics significantly influence the intelligent public transport system aspects: ICT, IoT, integration, safety and security, and smart accessibility and mobility. The result can be used to develop recommendations for improvements in the Trans Banyumas service related to intelligent public transportation system technology. However, implementing an intelligent public transport system in the Trans Banyumas service cannot be done individually. Therefore, there needs to be cooperation from both the government and the private sector to promote sustainable transportation, reduce the use of private vehicles, and minimize environmental impacts
Az oktatás és a pályaelhagyás, valamint a pályamódosítás kapcsolata az egészségügy területén
No full textThe choice of topic was inspired by thirty years of experience in the profession and the changes that have occurred during this time. Examining the relationship between education and career abandonment and career change in the field of healthcare and finding an alternative to the shortage of professionals. The research and its processing can explain the low number of qualified workers in the Hungarian healthcare system. A quantitative questionnaire survey was conducted among students in the healthcare field. 200 full-time and adult healthcare students currently enrolled in the study were included in the study in Budapest and 3 rural towns in the 2023/2024 academic year. A 1-month deadline was available for completion. Using a quantitative method, with online questionnaire sampling. Using Google Forms, 23 questions were asked, which included 13 closed-ended questions, 1 semi-closed-ended question and 9 Likert-scale definitions. They had to rate their answers to the questions from 1 to 5, where one meant very dissatisfied and five meant very satisfied. The processing of the questionnaire can help understand the reasons for career abandonment and career change and can show if these reasons include shortcomings in training. The research investigated whether insufficient knowledge or missed career orientation, insufficient knowledge of the profession when choosing a career could cause the current severe shortage of professionals in healthcare, as well as career abandonment and career change after training. The hypotheses concerned this, as well as the lack of financial and moral appreciation, which is also present in public consciousness, as the cause of the problem. Descriptive statistical analysis, career orientation, and familiarization with the profession are the keys to keep students in their future careers. The respondents were between the ages of 14 and 51 years old. The number and proportion of students participating in adult education is exceptionally high. When assessing the training, the number of satisfied people who rated it as good or excellent was very high (average of ratings: 4.33). The students who completed the questionnaire considered that the vocational instructor was competent in the given field (average of ratings: 4.52). It is encouraging that a significant number of respondents do not plan to leave their careers (160 people) or change careers (131 people). The lack of financial (average of ratings: 3.87) and professional (average of ratings: 3.6) appreciation is significantly felt in the responses. A significant number of students in the training do not plan to work abroad after completing their studies.A témaválasztást a szakmában eltöltött harminc év tapasztalata és az ezen idő alatt lezajlott változások inspirálták. Az oktatás és a pályaelhagyás, valamint a pályamódosítás kapcsolatának vizsgálata az egészségügy területén és választ keresése a szakemberhiányra. A kutatás és annak feldolgozása révén magyarázat adható a magyar egészségügyben tapasztalható szakképzett dolgozók alacsony létszámára. Kérdőíves kvantitatív kutatás készült az egészségügyi szakon résztvevő hallgatók között. A vizsgálatba 200 fő nappali és felnőtt egészségügyi képzésben jelenleg résztvevő hallgatót sikerült bevonni Budapesten és 3 vidéki városban a 2023/2024-es tanévben. A kitöltésre 1 hónapos határidő állt rendelkezésre. Kvantitatív módszert alkalmazva, online kérdőíves mintavétellel. A Google Forms segítségével 23 kérdés, ami 13 db zárt végű, 1 db félig zárt végű kérdést és 9 db Likert-skála szerinti meghatározást tartalmazott. A kérdésekre adott válaszaikat 1-től 5-ig kellett pontozniuk, ahol az egyes a nagyon elégedetlen, az ötös a nagyon elégedett választ jelentette. A kérdőív feldolgozása segíthet megérteni a pályaelhagyás és a pályamódosítás okait és megmutathatja, ha ezen okok között a képzés hiányosságai is szerepelnek. A kutatás azt vizsgálta, hogy a hiányos ismeretet adó vagy a kimaradt pályaorientáció, a nem kellően megismert szakma a pályaválasztáskor okozhatja-e az egészségügyben a napjainkban tapasztalható erőteljes szakemberhiányt, illetve a képzés utáni pályaelhagyást, pályamódosítást. A hipotézisek erre vonatkoztak, illetve a köztudatban is jelenlévő anyagi és erkölcsi megbecsülés hiánya, mint a probléma oka. A leíró statikai elemzés, a pályaorientáció, a szakma megismertetése a kulcs a tanulók későbbi pályán tartásához. A kitöltők 14-51 év közötti korcsoportban vettek részt a kutatásban. Kiemelkedően magas a felnőttképzésen résztvevő hallgatók száma, aránya. A képzés megítélésénél nagyon magas volt az elégedettek száma, akik jónak vagy kiválónak értékelték (értékelések átlaga: 4,33). A kérdőívet kitöltő hallgatók úgy ítélték meg, hogy a szakoktató kompetens az adott szakterületen (értékelések átlaga: 4,52). Reményteli, hogy a válaszadók jelentős száma nem tervezi sem a pályaelhagyást (160 fő), sem a pályamódosítást (131 fő). Az anyagi (értékelések átlaga: 3,87) és a szakmai (értékelések átlaga: 3,6) megbecsülés hiánya jelentősen érezhető a válaszoknál. A képzésben tanulók jelentős számban nem terveznek külföldi munkavállalást a tanulmányaik befejezése után
Experiencing and Interpreting Disability (Studies) in the Post-Socialist Era — Hungarian scholars in international disability (studies) discourses
No full textIntroduction
Although the powerful slogan "Nothing About Us Without Us!" originates from Central-Eastern Europe (Charlton, 2000), most scholars in the area arrived significantly later in the international disability studies arena. Despite some exceptions (see Prof. Dr. György Könczei, n.d.), scholars first entered the international disability studies discourse around the beginning of the 2000s. Nowadays, numerous resources provide several reasons for the delay, for example, Petri & Hruskó (2024), Hoffmann & Flamich (2024), Mladenov & Petri (2019), and Hoffmann & Flamich (2015). This paper is not intended to be one of them. In this paper, rather than seeking further explanations, we highlight aspects and ideas that Hungarian scholars have contributed to the theories and practices of multifaceted disability studies.
This article features scholars who represented Hungary at the 13th ALTER conference, held at the University of Innsbruck from July 8 to 10, 2025. However, before getting acquainted with the scholars and their talks, we take a closer look at ALTER, its brief history, aims, and philosophy.