TY - JOUR AU - Kuglics, Lajos AU - Géczy, Attila AU - Dusek, Karel AU - Busek, David AU - Illés, Balázs György TI - Personal Air-Quality Monitoring with Sensor-Based Wireless Internet-of-Things Electronics Embedded in Protective Face Masks JF - SENSORS J2 - SENSORS-BASEL VL - 24 PY - 2024 IS - 8 SP - 2601 SN - 1424-8220 DO - 10.3390/s24082601 UR - https://m2.mtmt.hu/api/publication/34799188 ID - 34799188 AB - In this paper, the design and research of a sensor-based personal air-quality monitoring device are presented, which is retrofitted into different personal protective face masks. Due to its small size and low power consumption, the device can be integrated into and applied in practical urban usage. We present our research and the development of the sensor node based on a BME680-type environmental sensor cluster with a wireless IoT (Internet of Things)-capable central unit and overall low power consumption. The integration of the sensor node was investigated with traditional medical masks and a professional FFP2-type mask. The filtering efficiency after embedding was validated with a head model and a particle counter. We found that the professional mask withstood the embedding without losing the protective filtering aspect. We compared the inner and outer sensor data and investigated the temperature, pressure, humidity, and AQI (Air Quality Index) relations with possible sensor data-fusion options. The novelty is increased with the dual-sensor layout (inward and outward). It was found that efficient respiration monitoring is achievable with the device. With the analysis of the recorded data, characteristic signals were identified in an urban environment, enabling urban altimetry and urban zone detection. The results promote smart city concepts and help in endeavors related to SDGs (Sustainable Development Goals) 3 and 11. LA - English DB - MTMT ER - TY - JOUR AU - Gál, Márton AU - Samaniego Andrade, Samantha Kathiuska AU - Fehér, Anna Éva AU - Farkas, Attila AU - Madarász, János AU - Horváth, Lili AU - Gordon, Péter AU - Kovács, Róbert Sándor AU - Nagyné László, Krisztina TI - Thermal diffusity in copper benzene-1,3,5-tricarboxylate–reduced graphite oxide mechanical composites JF - JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY J2 - J THERM ANAL CALORIM PY - 2024 PG - 13 SN - 1388-6150 DO - 10.1007/s10973-024-13021-x UR - https://m2.mtmt.hu/api/publication/34772009 ID - 34772009 N1 - Funding Agency and Grant Number: Nemzeti Kutatsi Fejlesztsi s Innovcis Hivatal [2020-3.1.1-ZFR-KVG-2020-00006]; National Research, Development and Innovation Fund of Hungary [2020-3.1.2-ZFR-KVG]; Hungarian grants [OTKA K143571, FK134277, TKP-6-6/PALY-2021]; Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund [TKP2021-NVA]; Sustainable Development and Technologies National Programme of the Hungarian Academy of Sciences (FFT NP FTA); Stipendium Hungaricum scholarship program of the Hungarian Government Funding text: We extend our warm thanks to G. Bosznai (BME) for the invaluable technical assistance. This work was performed in the frame of the 2020-3.1.1-ZFR-KVG-2020-00006 project, implemented with the support provided from the National Research, Development and Innovation Fund of Hungary, financed under the 2020-3.1.2-ZFR-KVG funding scheme. This research was also funded by the Hungarian grants OTKA K143571 and FK134277. The research is part of project no Project no. TKP-6-6/PALY-2021 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-NVA funding scheme. The research was also funded by the Sustainable Development and Technologies National Programme of the Hungarian Academy of Sciences (FFT NP FTA). SKSA is grateful to the Stipendium Hungaricum scholarship program of the Hungarian Government. AB - Metal organic frameworks (MOFs) and particularly copper benzene-1,3,5-tricarboxylate (HKUST-1) are excellent materials for gas storage (e.g., CH 4 , N 2 , H 2 adsorption) and gas separation. In this work, reduced graphene oxide (RGO)–HKUST-1 mechanical mixtures were studied in order to reveal the effect of RGO content on the pressure tolerance of the texture and heat conductivity. HKUST-1 was obtained by two different synthesis routes. Air-dried MOF and RGO were thoroughly mixed prior to the compression. Powder XRD and Raman spectroscopy were used to characterize the response of the crystal structure, while low-temperature nitrogen adsorption was used the follow the adsorption properties of the pellets. Finally, the "flash" heat pulse method was used to assess the thermal properties. The gas adsorption isotherms revealed that the adsorption capacity decreases when RGO is added. Based on Raman and XRD results, we found that the synthesis route has an effect on multiple scales. We experimentally confirmed that evaluation of the thermal diffusivity requires a model more complex than the simple Fourier equation, due to the inherent heterogeneous structure of the material. A good approximation of the Fourier coefficient of thermal diffusivity was obtained using the parameters of the Guyer–Krumhansl equation. The heat pulse experiments also revealed possible size-dependent behavior. LA - English DB - MTMT ER - TY - JOUR AU - Harsányi, Gábor AU - Poppe, András AU - Hegedüs, János AU - Hantos, Gusztáv AU - Bojta, Péter AU - Kovacs, Robert TI - Climatically Accelerated Material Processes Determining the Long-Term Reliability of Light-Emitting Diodes JF - MATERIALS J2 - MATERIALS VL - 17 PY - 2024 IS - 7 PG - 20 SN - 1996-1944 DO - 10.3390/ma17071643 UR - https://m2.mtmt.hu/api/publication/34767534 ID - 34767534 N1 - Funding Agency and Grant Number: European Union [101007319]; AI-TWILIGHT project; Hungarian government through National Research, Development and Innovation Fund [2019-2.1.3-NEMZ_ECSEL-2021-00008] Funding text: The work presented has received funding from the European Union's Horizon 2020 researchand innovation programme through the H2020 ECSEL project AI-TWILIGHT (grant agreementnumber: 101007319). Co-financing of the AI-TWILIGHT project. Co-financing of the AI-TWILIGHT project by the Hungarian government through the 2019-2.1.3-NEMZ_ECSEL-2021-00008 grant of the National Research, Development and Innovation Fund is also acknowledged. AB - LEDs (Light-Emitting Diodes) are widely applied not only in decorative illumination but also in everyday lighting in buildings, flats, public areas, and automotive fields. These application areas often mean harsh environments, for example, regarding the humidity content of the surrounding air: besides outdoor and automotive illumination, even the household use cases (kitchen, bathroom, cellar) may represent extreme temperature and humidity variations (often reaching relative humidity levels close to 100%) for these devices; thus, their reliability behaviour in such circumstances should be better understood. Thermally activated processes were studied in several previous publications, but less information is available regarding high-humidity environmental tests. Moisture and temperature ageing tests with appropriate environmental parameter settings were performed as accelerated lifetime tests to investigate not only the effect of temperature but also that of humidity on the ageing and reliability of LED packages containing RGB (red green blue) chips and phosphor-converted white (pcW) LEDs. The ageing was followed not only through monitoring optical/electrical/spectral parameters but also with material analysis. Moisture–material interaction models were proposed and set up. It was found that humidity-accelerated ageing processes are more severe than expected from previous assumptions. RGB and pcW LEDs showed strongly different behaviour. LA - English DB - MTMT ER - TY - JOUR AU - Havellant, Gergő AU - Illés, Balázs György AU - Busek, David AU - Géczy, Attila TI - Improving efficiency of vapour phase soldering ovens with pressure and temperature-based process monitoring JF - CASE STUDIES IN THERMAL ENGINEERING J2 - CASE STUD THERM ENG VL - 57 PY - 2024 PG - 9 SN - 2214-157X DO - 10.1016/j.csite.2024.104315 UR - https://m2.mtmt.hu/api/publication/34757552 ID - 34757552 N1 - Department of Electronics Technology, Faculty of Electrical Engineering and Informatics, Budapest University of Technology and Informatics, Hungary Łukasiewicz Research Network, Institute of Microelectronics and Photonics, LTCC Research Group, Kraków, Poland Department of Electrotechnology, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic Export Date: 5 April 2024 Correspondence Address: Illés, B.; Department of Electronics Technology, Hungary; email: illes.balazs@vik.bme.hu Funding details: Nemzeti Kutatási Fejlesztési és Innovációs Hivatal, NKFIH, FK 132186, ÚNKP-23-2-I-BME-244 Funding details: Narodowym Centrum Nauki, NCN, 2022/47/B/ST5/00997 Funding text 1: This research was partially supported by the National Research, Development and Innovation Office- NKFIH, project no. FK 132186 and no. ÚNKP-23-2-I-BME-244; and by the National Science Center Poland (NCN) project no. 2022/47/B/ST5/00997. LA - English DB - MTMT ER - TY - JOUR AU - Farkas, Csaba AU - Gál, László AU - Csiszár, András AU - Grennerat, Vincent AU - Jeannin, Pierre-Olivier AU - Xavier, Pascal AU - Rigler, Dániel AU - Krammer, Olivér AU - Plachy, Zbynek AU - Dusek, Karel AU - Kovács, Róbert Sándor AU - Fehér, Anna Éva AU - Géczy, Attila TI - Sustainable printed circuit board substrates based on flame-retarded PLA/flax composites to reduce environmental load of electronics: Quality, reliability, degradation and application tests JF - SUSTAINABLE MATERIALS AND TECHNOLOGIES J2 - SUSTAINABLE MATERIALS TECHNOLOGIES VL - 40 PY - 2024 PG - 15 SN - 2214-9929 DO - 10.1016/j.susmat.2024.e00902 UR - https://m2.mtmt.hu/api/publication/34746761 ID - 34746761 AB - The present paper introduces a novel, sustainable approach to produce an eco-friendly Printed Circuit Board (PCB) substrate; a substitute for traditional substrates, to significantly reduce e-waste. We present the prepreg technology, the road to actual circuit assembly with application studies, life cycle analysis (LCA), and sustainability analysis. The flame-retarded prepregs and resulting PCB assemblies were based on polylactic acid (PLA), the structure is reinforced with flax textiles. After copper lamination, subtractive PCB production was performed, and thermal and mechanical reliability was investigated in the case of both laminated and bare substrates. Steps of surface roughness, peel and thermal analysis followed. After a new set of assemblies, the post-assembly analysis was extended with further shear strength analysis on the soldered components and mass analysis regarding thermal processes. The evaluation showed that PLA/Flax substrates provide reliable structural performance up to 200 °C in the reflow soldering process; this allows limited but stabilized application possibilities with specific eco-friendly lead-free solders. A basic blinker circuit and a field programmable gate array (FPGA)–based design was produced and tested; the latter has the general complexity of a commercial circuit. A vol% and wt% analysis extended our discussion with a reduction of harmful components in waste in the range of 90%, which is a disruptive and significant result. Life cycle analysis (LCA) quantified the ecological impact of the assembly, highlighting a significant ease on environmental load (∼10%) for the total assembly. Finally, a qualitative degradation study was introduced to the prepared samples to investigate short-term stability with mechanical-, colour-, mass- and scanning electron microscopy (structure) analysis. Early results show that the boards can withstand the harsh environment of a composting bin for a few days, but in the time of a few weeks, degradation starts, pointing to eventual decomposition. The work directly connects with multiple sustainability development goals. © 2024 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Borkovits, B. AU - Kontsek, Endre AU - Pesti, Adrián István AU - Gordon, Péter AU - Gergely, Szilveszter AU - Csabai, I. AU - Kiss, András AU - Pollner, Péter TI - Classification of colorectal primer carcinoma from normal colon with mid‐infrared spectra JF - JOURNAL OF CHEMOMETRICS J2 - J CHEMOMETR PY - 2024 PG - 15 SN - 0886-9383 DO - 10.1002/cem.3542 UR - https://m2.mtmt.hu/api/publication/34745108 ID - 34745108 AB - In this project, we used formalin‐fixed paraffin‐embedded (FFPE) tissue samples to measure thousands of spectra per tissue core with Fourier transform mid‐infrared spectroscopy using an FT‐IR imaging system. These cores varied between normal colon (NC) and colorectal primer carcinoma (CRC) tissues. We created a database to manage all the multivariate data obtained from the measurements. Then, we applied classifier algorithms to identify the tissue based on its yielded spectra. For classification, we used the random forest, a support vector machine, XGBoost, and linear discriminant analysis methods, as well as three deep neural networks. We compared two data manipulation techniques using these models and then applied filtering. In the end, we compared model performances via the sum of ranking differences (SRD). LA - English DB - MTMT ER - TY - JOUR AU - Sharma, Ravi AU - Villányi, Balázs János TI - An Efficient and Dependable UAV-Assisted Code Dissemination in 5G-Enabled Industrial IoT JF - IEEE OPEN JOURNAL OF THE COMMUNICATIONS SOCIETY J2 - IEEE OPEN J COMMUN SOC VL - 5 PY - 2024 SP - 1525 EP - 1536 PG - 12 SN - 2644-125X DO - 10.1109/OJCOMS.2024.3368275 UR - https://m2.mtmt.hu/api/publication/34726787 ID - 34726787 N1 - Export Date: 8 March 2024 AB - The Industrial Internet of Things (IIoT) has infiltrated our culture and is gaining traction in a variety of industrial applications. All of this is made possible by the use of 5G-connected massive Intelligent Sensing Devices (ISDs) and software-defined technology. It is sometimes desirable, and even required, to upgrade these ISDs without replacing hardware to make them smarter by adding new features and/or removing bugs through code dissemination. Using moving vehicles of the 5G-enabled Internet of Vehicles (IoV) infrastructure is one possible and efficient way to disseminate code. Specifically, safe code dissemination through a large number of vehicles in a 5G network has emerged as a critical issue. The motivation stems from the limitations of existing methods, often centralized and vulnerable to compromise, particularly in semi-connected networks. Therefore, this paper proposes an efficient and reliable Unmanned Aerial Vehicle (UAV)-assisted digital signature-based safe code dissemination framework for a 5G-enabled IIoT system. Our decentralized approach, which uses digital signatures and a Subjective Logic model, not only ensures code integrity but also identifies credible code mules, avoiding the pitfalls of traditional trust evaluation schemes. Furthermore, for UAV trajectory optimization, we redesign the trajectory with virtual waypoints to shorten the trajectory path for upgrading ISDs that were not upgraded due to the long-time trailing phenomenon. Our approach is useful in scenarios such as smart cities, where ISDs lack communication facilities. Through extensive experiments, our framework demonstrates superior efficiency and reliability compared to state-of-the-art methods. Authors LA - English DB - MTMT ER - TY - CHAP AU - Illés, Balázs György AU - Choi, Halim AU - Skwarek, Agata TI - Development and Characterization of Sn99Ag0.3Cu0.7-(ZrO2/CuO/TiO2) Nano-Composite Solder Alloys T2 - 2024 Pan Pacific Strategic Electronics Symposium (Pan Pacific) PB - Surface Mount Technology Association (SMTA) CY - Eden Prairie (MN) SN - 9781944543204 PY - 2024 SP - 91 EP - 98 PG - 8 DO - 10.23919/PanPacific60013.2024.10436525 UR - https://m2.mtmt.hu/api/publication/34656961 ID - 34656961 N1 - Budapest University of Technology and Economics, Faculty of Electrical Engineering and Informatics, Department of Electronics Technology, Budapest, Hungary Lukasiewicz Research Network, Institute of Microelectronics and Photonics, LTCC Technology Research Group, Kraków, Poland Conference code: 197496 Export Date: 18 March 2024 Correspondence Address: Illes, B.; Budapest University of Technology and Economics, Hungary Funding details: Narodowym Centrum Nauki, NCN, 2022/47/B/ST5/00997 Funding text 1: This work was supported by the National Science Center Poland (NCN) project no. 2022/47/B/ST5/00997. AB - The 'lead-free' change in the soldering technology caused the widespread application of the SnAgCu (SAC) solder alloys. The so-called low Ag content ones, like Sn99Ag0.3Cu0.7 (SAC0307) and Sn98.5Ag1Cu0.5 (SAC105), are more and more popular recently due to their good price and thermo-mechanical properties. The most novel solution to further improve the solder alloys' properties is adding nano-sized ceramic reinforcement particles into the solder alloys. This procedure results in, nano-composite'' solder joints. A wide range of ceramic nano-particles (NPs) was already tested, like Fe2O3, TiO2, Si3Ni4, ZrO2, Al2O3, SiC, La2O3, etc. The reinforcement particles improve the solder joints' mechanical properties (shear force, yield strength, microhardness, etc.), with some Kelvin of increase in the liquidus-Temperature of the alloy. It is generally accepted that mechanical improvement is caused by dispersion-strengthening mechanisms. The ceramic nano-particles are not soluble in the Sn, so they incorporate at the intermetallic (Cu6Sn5, CU3Sn, and Ag3Sn) grains and at the Sn grain boundaries, where they enhance heterogeneous nucleation. This effect suppresses the grain growth (all phases) and decreases dislocation motions. In the present study, the effect of three oxide ceramics (TiO2, ZrO2, and CuO) as reinforcements in 0.25wt% weight fraction was investigated on the quality and reliability of the composite SAC0307 solder alloy. The primary particle size of NPs was between 20-100nm. The NPs were mixed into the solder paste. Standard spread tests of the different alloys were done on FR4 laminates covered by Cu foil and imm-Ag surface finishing over on it. Solder joints were prepared from the alloys and 0603 chip resistors by convectional surface mounting technology on FR4-based printed circuit boards with imm-Ag surface finish. The shear strength of the chip resistors was measured. The solder joints were loaded with 4000 hours 85°C/85RH% climatic test to investigate their corrosion resistance. The results showed that NPs slightly decreased the wettability of nano-composite solder alloys. The shear strength of the composite joints generally increased, which proved that the second phase dispersion strengthening mechanism worked. However, the NPs have different effects on the corrosion resistance of the composite alloys. A former study proved that TiO2 could increase corrosion resistance [13]. Now it was observed that ZrO2 did not change it, and CuO decreased it considerably. In correlation with corrosion resistance, the different composite alloys produced different amounts of Sn whiskers during the corrosive climate test. © 2024 SMTA. LA - English DB - MTMT ER - TY - JOUR AU - I Made, Putrama AU - Martinek, Péter TI - Self-supervised data lakes discovery through unsupervised metadata-driven weighted similarity JF - INFORMATION SCIENCES J2 - INFORM SCIENCES VL - 662 PY - 2024 PG - 19 SN - 0020-0255 DO - 10.1016/j.ins.2024.120242 UR - https://m2.mtmt.hu/api/publication/34556952 ID - 34556952 N1 - Export Date: 19 February 2024 CODEN: ISIJB Correspondence Address: Putrama, I.M.; Department of Electronics Technology, Hungary; email: putrama.imade@edu.bme.hu LA - English DB - MTMT ER - TY - JOUR AU - Bonyár, Attila AU - Nagy, Ágoston Gábor AU - Gunstheimer, Hans AU - Fläschner, Gotthold AU - Horváth, Róbert TI - Hydrodynamic function and spring constant calibration of FluidFM micropipette cantilevers JF - MICROSYSTEMS & NANOENGINEERING J2 - MICROSYST NANOENG VL - 10 PY - 2024 PG - 10 SN - 2055-7434 DO - 10.1038/s41378-023-00629-6 UR - https://m2.mtmt.hu/api/publication/34556904 ID - 34556904 N1 - Funding Agency and Grant Number: Lendulet (HAS) research program; National Research, Development and Innovation Office of Hungary (VEKOP) [TKP2021-EGA-02]; National Research, Development, and Innovation Fund of Hungary [KKP_19KKP 129936]; Hungarian Academy of Engineering; MICHELBERGER MESTERDJ Scholarship; [TKP2021-EGA-04] Funding text: This work was supported by the "Lendulet" (HAS) research program, the National Research, Development and Innovation Office of Hungary (VEKOP, ELKH topic-fund, "Elvonal" KKP_19KKP 129936 and KH grants, TKP2021-EGA-04 program financed from the NRDI Fund). The research performed at the Budapest University of Technology and Economics was funded by the National Research, Development, and Innovation Fund of Hungary under Grant TKP2021-EGA-02. We would like to express our thanks to Dr. Torsten Mueller from Bruker Nano GmbH for measuring the properties of a micropipette cantilever with their JPK NanoWizard instrument. We would like to express our thanks to Dr. Zoltan Hajnal and Norbert Pap for their help in constructing the 3D model of the cantilever and to Dr. Dario Ossola from Cytosurge AG for his helpful suggestions in formulating the manuscript. A. Bonyar is also grateful for the support of the Hungarian Academy of Engineering and the "MICHELBERGER MESTERD & Iacute;J" Scholarship. LA - English DB - MTMT ER -