Periodica Polytechnica (Budapest University of Technology and Economics)
Not a member yet
22160 research outputs found
Sort by
Good practices and recommendations to Enhancing Education with Gamified Open Badges
No full textThe objective of this article is to explore how gamified open badges can enhance motivation and engagement in education through a qualitative desk research methodology. It aims to explain the concept of gamification in education, differentiate between digital badges and microcredentials, discuss motivational frameworks, present good practices for implementing badges, showcase successful case studies, and identify the main providers of micro-credentials. By doing so, the article provides valuable insights and practical guidance for educators and stakeholders on leveraging gamified open badges to improve the learning experience
Improvement of Effectiveness and Photocatalytic Properties of Poly(vinylidene Fluoride)-TiO2-WO3 Membrane with Polydopamine Modification for Natural Rubber Wastewater Treatment
Get PDFThis study investigates the enhancement of poly(vinylidene fluoride) (PVDF) membranes modified with TiO2, tungsten trioxide, and coated with polydopamine (PDA) for rubber industry wastewater treatment. PDA coating improved the adhesion and dispersion of photocatalyst particles on the PVDF membrane. Membrane characterization using FTIR, SEM, SEM-EDX, XRD, mechanical strength, porosity, pore size analysis, water contact angle, and water uptake confirmed the structural and surface property enhancements of the PVDF-TiO2-WO3/PDA membrane, which contributed to improved pollutant rejection performance. The PVDF-TiO2-WO3/PDA membrane enhanced ammonia, phenol, chemical oxygen demand, and total dissolved solids rejection by 98.22%, 99.39%, 87.18%, and 51.06%, respectively, compared to the pristine PVDF membrane. After pretreatment, the flux value was 154.32 L/m2·h. The membrane exhibited the best photocatalytic degradation activity, with TiO2-WO3 nanoparticles enhancing pollutant removal under visible light and PDA coating contributing to enhanced selective permeability. Kinetic studies indicated that the zero-order kinetic model best describes photocatalytic activity. Membrane performance remained stable over five cycles, with high pollutant rejection despite some pore blockage and swelling. Overall, PDA modification on PVDF-TiO2-WO3 membranes offers a promising solution for efficient and environmentally friendly rubber wastewater treatment
An Ontology-based Approach to Solving the Digital Representation Problem in Architectural Engineering
Get PDFThis article addresses the need for computer-aided design systems in Architectural Engineering (AE) design for building construction, an essential aspect of every building's design that is currently underserved by existing software solutions. First, we analyse the various challenges facing the development of better tools and propose that a fundamental problem of representation lies behind most of them. Next, we suggest a desideratum for representing building constructions digitally in our tools, and we argue that a formal ontology is best suited for the task. Numerous systems have been proposed for developing ontologies, many of which rely on a domain-independent upper ontology. This common upper layer supports the creation of more specific ontologies in an interoperable and mutually supportive way. The BFO upper ontology and the corresponding methodology are briefly introduced, followed by a review of many existing ontologies relevant to AE. Lastly, we introduce a prototype proto-ontology for describing building constructions and their related phenomena: the building construction ontology. We present the most important terms and modules of BCON and then demonstrate its use through a small case study of a relatively simple construction detail. Finally, we highlight the many possible applications of such a representational system
From Experimental Investigation to Optimized Design: A Time-efficient Methodology for Carbon Fiber Composite Crash Structures in Formula Student Applications
Get PDFThis study presents the design and numerical validation of a composite impact attenuator, with Formula Student serving as a proof of concept. The research methodology involved an initial calibration phase, where simulations of simple test geometries were iteratively refined to match experimental data from dynamic tests within a 1% error margin. These validated material parameters were then applied to a final impact attenuator design featuring a five-tube configuration. To enhance time and cost efficiency, physical testing was conducted only at the intermediate component level, where simulation models were calibrated. The final crash structure was then optimized entirely through virtual simulations, eliminating the need for full-scale physical prototyping. Finite element simulations demonstrated that the proposed structure meets established deceleration and energy dissipation criteria with a significant safety margin. Additionally, compared to a commercially available aluminum honeycomb attenuator, the composite design achieved equivalent energy absorption characteristics while reducing weight by 13%. These findings validate the proposed methodology and highlight the advantages of composite crash structures for high-performance applications
MKE90: Avagy hivatásunk múltja, jelene, jövője a trendek, kihívások és az igények tükrében
No full textComparative Study between Common and Individual MPPT Controller Using Fuzzy Logic Control for Hybrid System (Photovoltaic/Wind Energy Conversion System)
Get PDFThis paper aims to hybridize photovoltaic systems (PVs) with wind energy conversion systems (WECs) by using different architectures, with a comparative study to distinguish the best hybridization method that gives the best performance. The first architecture uses an individual maximum power point tracking (MPPT) controller for each system independently. The photovoltaic generator is connected to the DC/DC converter and is controlled by fuzzy logic control (FLC) to track maximum power. In the WECs system, which is based on a permanent magnet synchronous generator (PMSG), the DC/DC converter is also controlled by FLC to maximize its output power. The second architecture uses a single MPPT controller for both systems; the PV generator and AC/DC converter of the WECs are connected to a common DC/DC converter controlled by the FLC. The hybrid system is connected to the grid via an inverter, which is controlled by voltage-oriented control (VOC) to separate the control of the active and reactive powers. The system studied was specially designed to be installed in the building, consisting of a photovoltaic system providing 25 kW and a WECs composed of three small turbines, each providing 8.5 kW. The MATLAB simulation results are presented under varying conditions of sunlight, wind speed, and load requirement, proving that; the using of an individual MPPT controller gives better performances than the single MPPT controller. However, the last topology provides more power than the first topology (over 1 kW) because of the reduced number of converters used
Unsteady Magneto-radiative Flow of Copper-water Nanofluid Over an Exponentially Stretching Surface
Get PDFUnderstanding the complex behavior of fluid flows under various physical influences is crucial for advancing engineering and industrial applications. This paper presents the investigation of the unsteady, incompressible, single-phase magneto-radiative flow of a copper-water nanofluid over an exponentially stretching surface, considering the effects of viscous dissipation and temperature-dependent heat sources. This model, proposed in the present analysis, is based on fundamentals of the continuity and Navier–Stokesequations with mass conservation. Further, use of a similarity transformation will reduce the equations to dimensionless form and provide a numerical solution using the Runge–Kutta–Fehlberg method. In physics, engineering, and industrial applications, the most interesting parameters are the velocity, temperature, skin friction, and the Nusselt number (Nu). The results of this study are compared with previous works, showing significant agreement with findings under similar conditions. The analysis reveals that both temperature and velocity boundary layer increase when all very specific effects of radiation (R), heat source (Q), copper nanoparticle volume fraction, and magnetic field strength parameter are present. On the other hand, it is found that skin friction increases when considering both copper nanoparticle volume fraction and magnetic field strength parameter, but the Nu decreases if R, Q, copper nanoparticle volume fraction, and magnetic field strength parameter are the factors responsible for that. These outcomes will be further delineated through graphics and be elaborated in engineering and industrial context
Integration of Piezoelectric Wafer Sensors PWS Signal to Generate Ultrasonic Guided Waves in Planar and Cylindrical Waveguide
Get PDFThis paper explores the integration of piezoelectric wafers as both generators and receivers of ultrasonic-guided waves in planar and cylindrical waveguides. To this end, a ceramic Piezoelectric single crystal (PZT) generates mechanical waves in the structure. The experimental setup is thoroughly described, and the emitted signals are compared with those from two ultrasonic transducers to ensure signal integrity. A 1D Fast Fourier transform is utilized to monitor the resonant frequency of the generated waves. The study focuses on two types of waveguides: a multi-layer fiberglass composite plate [0° 90°]6 and a single-layer stainless steel pipeline. For each structure, a specific layout of PZT wafers is established to analyze the propagation of guided ultrasonic waves. The results show that PZT wafers effectively generated guided wave modes, allowing for the inspection of structural integrity in both the composite plate and pipeline. Notably, the signals were captured without any loss of information, highlighting the advantages of PZT wafers, including their consistent vibration frequency, simple use, and excellent contact with both flat and curved surfaces. This demonstrates the potential of PWS technology for reliable non-destructive testing in complex structures
Improving the Sustainability of Individual, Motorised Transport by Implementing E-government System
Get PDFPresent day's world is dominated by a set of problems that affect almost all aspects of people's lives (e.g. energy crisis, labor shortages, inflation, etc.). These challenges also have a major impact on transport through its institutional-economic-social interactions. The institutional environment also has a significant impact on the transport system, due to the two-way nature of the systemic interactions. This makes it particularly important to examine the transport aspect of the digitalization of procedures in public administration institutions. The research develops a methodology to quantify the transport energy savings and to increase the sustainability of mobility by developing SMART solutions already applied in public administration, which is presented through a case study in Hungary