TY - JOUR AU - Farkas, Márton AU - Rózsa, Szabolcs AU - Vanek, Bálint TI - Multi-sensor Attitude Estimation using Quaternion Constrained GNSS Ambiguity Resolution and Dynamics-Based Observation Synchronization JF - ACTA GEODAETICA ET GEOPHYSICA J2 - ACTA GEOD GEOPHYS VL - 59 PY - 2024 IS - 1 SP - 51 EP - 71 PG - 21 SN - 2213-5812 DO - 10.1007/s40328-024-00441-2 UR - https://m2.mtmt.hu/api/publication/34832889 ID - 34832889 N1 - Institute for Computer Science and Control, Eötvös Lóránd Research Network, Kende u. 13-17, Budapest, 1111, Hungary Department of Geodesy and Surveying, Faculty of Civil Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3, Budapest, 1111, Hungary Export Date: 3 May 2024 Correspondence Address: Farkas, M.; Institute for Computer Science and Control, Kende u. 13-17, Hungary; email: mfarkas@sztaki.hu AB - Recently, high accuracy and low-cost navigation hardware is becoming increasingly available that can be efficiently used for the control of autonomous vehicles. We present a sensor fusion method providing tightly coupled integration of pseudorange, carrier phase, and Doppler satellite measurements taken at multiple vehicle-mounted GNSS antennas with onboard inertial sensor observations. The key of accurate GNSS position and orientation estimation is the successful integer ambiguity resolution. We propose a method that uses the quaternion states as constraints to improve ambiguity resolution and to increase the accuracy of the GNSS based attitude determination. Generally, the low-cost hardware neither allows a hardware-level time synchronization between the GNSS receivers due to a lack of a common external oscillator nor provides the clock steering function available in geodetic GNSS receivers. The lack of observation synchronization causes several degrees of error in attitude estimation. To eliminate this effect, a dynamics-based solution is presented that synchronizes the observations by taking the dynamics of the moving platform into account. Compared to common external oscillator based sensor setups, our solution allows to increase both the number of rover receivers on the platform and the baselines between them easily, thus it opens up new possibilities in the attitude determination of large vehicles. We validate our approach against a tactical grade inertial navigation system. The results show that our approach using low-cost sensors provides the ambiguity success rate of 100% for the moving baselines, and the positioning and attitude error reached the centimeter and half a degree level, respectively. © The Author(s) 2024. LA - English DB - MTMT ER - TY - JOUR AU - Tóth, Gyula TI - IAG Newsletter JF - JOURNAL OF GEODESY J2 - J GEODESY VL - 98 PY - 2024 IS - 4 PG - 4 SN - 0949-7714 DO - 10.1007/s00190-024-01840-7 UR - https://m2.mtmt.hu/api/publication/34832876 ID - 34832876 N1 - Export Date: 3 May 2024 Correspondence Address: Tóth, G.; IAG Communication and Outreach Branch, Hungary LA - English DB - MTMT ER - TY - JOUR AU - Samuvel Raj, R AU - Arulraj, G Prince AU - Anand, N. AU - Kanagaraj, Balamurali AU - Lublóy, Éva Eszter TI - Nano-Bentonite as a Sustainable Enhancer for Alkali Activated Nano Concrete: Assessing Mechanical, Microstructural, and Sustainable Properties JF - Case Studies in Construction Materials J2 - CASE STUD CONSTR MAT VL - e PY - 2024 SP - e03213 SN - 2214-5095 DO - 10.1016/j.cscm.2024.e03213 UR - https://m2.mtmt.hu/api/publication/34824664 ID - 34824664 LA - English DB - MTMT ER - TY - JOUR AU - Gere, Dániel AU - Pomázi, Flóra AU - Szöllősi, Anna AU - Jahanpeyma, Pegah AU - Ermilov, Alexander Anatol AU - Baranya, Sándor AU - Toldy, Andrea TI - Mikroműanyag szennyezés vizsgálata a Duna budapesti szakaszán JF - POLIMEREK J2 - POLIMEREK VL - 10 PY - 2024 IS - 2 SP - 66 EP - 72 PG - 7 SN - 2415-9492 UR - https://m2.mtmt.hu/api/publication/34805619 ID - 34805619 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Szagri, Dóra TI - Hogyan befolyásolhatjuk otthonaink hőmérsékletét?. Hőhullámok a panellakásokban TS - Hőhullámok a panellakásokban JF - ÉLET ÉS TUDOMÁNY J2 - ÉLET ÉS TUDOMÁNY VL - 79 PY - 2024 IS - 12 SP - 366 EP - 368 PG - 3 SN - 0013-6077 UR - https://m2.mtmt.hu/api/publication/34804571 ID - 34804571 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Javed, M.F. AU - Muhammad, Fawad AU - Lodhi, R. AU - Najeh, T. AU - Gamil, Y. TI - Forecasting the strength of preplaced aggregate concrete using interpretable machine learning approaches JF - SCIENTIFIC REPORTS J2 - SCI REP VL - 14 PY - 2024 IS - 1 PG - 28 SN - 2045-2322 DO - 10.1038/s41598-024-57896-0 UR - https://m2.mtmt.hu/api/publication/34803148 ID - 34803148 N1 - Silesian University of Technology Poland, Gliwice, Poland Budapest University of Technology and Economics Hungary, Budapest, Hungary Department of Urban and Regional Planning, National University of Sciences and Technology (NUST), Islamabad, Pakistan Operation and Maintenance, Operation, Maintenance and Acoustics, Department of Civil, Environmental and Natural Resources Engineering, Lulea University of Technology, Lulea, Sweden Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Selangor, Bandar Sunway, 47500, Malaysia Department of Civil Engineering, Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, Swabi, 23640, Pakistan Export Date: 22 April 2024 Correspondence Address: Najeh, T.; Operation and Maintenance, Sweden; email: taoufik.najeh@ltu.se Correspondence Address: Javed, M.F.; Department of Civil Engineering, Pakistan; email: arbabfaisal@cuiatd.edu.pk Chemicals/CAS: water, 7732-18-5 AB - Preplaced aggregate concrete (PAC) also known as two-stage concrete (TSC) is widely used in construction engineering for various applications. To produce PAC, a mixture of Portland cement, sand, and admixtures is injected into a mold subsequent to the deposition of coarse aggregate. This process complicates the prediction of compressive strength (CS), demanding thorough investigation. Consequently, the emphasis of this study is on enhancing the comprehension of PAC compressive strength using machine learning models. Thirteen models are evaluated with 261 data points and eleven input variables. The result depicts that xgboost demonstrates exceptional accuracy with a correlation coefficient of 0.9791 and a normalized coefficient of determination (R2) of 0.9583. Moreover, Gradient boosting (GB) and Cat boost (CB) also perform well due to its robust performance. In addition, Adaboost, Voting regressor, and Random forest yield precise predictions with low mean absolute error (MAE) and root mean square error (RMSE) values. The sensitivity analysis (SA) reveals the significant impact of key input parameters on overall model sensitivity. Notably, gravel takes the lead with a substantial 44.7% contribution, followed by sand at 19.5%, cement at 15.6%, and Fly ash and GGBS at 5.9% and 5.1%, respectively. The best fit model i.e., XG-Boost model, was employed for SHAP analysis to assess the relative importance of contributing attributes and optimize input variables. The SHAP analysis unveiled the water-to-binder (W/B) ratio, superplasticizer, and gravel as the most significant factors influencing the CS of PAC. Furthermore, graphical user interface (GUI) have been developed for practical applications in predicting concrete strength. This simplifies the process and offers a valuable tool for leveraging the model's potential in the field of civil engineering. This comprehensive evaluation provides valuable insights to researchers and practitioners, empowering them to make informed choices in predicting PAC compressive strength in construction projects. By enhancing the reliability and applicability of predictive models, this study contributes to the field of preplaced aggregate concrete strength prediction. © The Author(s) 2024. LA - English DB - MTMT ER - TY - JOUR AU - Juhász, Károly Péter AU - Schaul, Péter AU - Veres, Boglárka TI - Numerical and experimental investigation on synthetic macrofiber-reinforced concrete manhole exposed to railway loads JF - Case Studies in Construction Materials J2 - CASE STUD CONSTR MAT VL - 20 PY - 2024 PG - 25 SN - 2214-5095 DO - 10.1016/j.cscm.2024.e03093 UR - https://m2.mtmt.hu/api/publication/34785837 ID - 34785837 N1 - Budapest University of Technology and Economics, Department of Mechanics, Materials and Structures, Műegyetem rakpart 1-3, Budapest, 1111, Hungary Budapest University of Technology and Economics, Department of Construction Materials and Technologies, Műegyetem rakpart 1-3, Budapest, 1111, Hungary Kodolányi János University, Business Administration and Management, Rákóczi utca 25, Székesfehérvár, 8000, Hungary JKP STATIC Ltd, Budapest, Hungary Export Date: 12 April 2024 Correspondence Address: Juhász, P.K.; JKP STATIC Ltd, Reitter Ferenc utca 100 B/2/4, Hungary; email: office@jkp.hu AB - The refurbishment of railway lines and the installation of new tracks necessitate the construction of numerous concrete manholes; therefore, the optimization of manholes should be investigated. To this end, the use of innovative materials in addition to advanced design methods with realistic modeling is required. In the case of conservatively designed structures, there exists the possibility of redesigning the structure utilizing suitable fiber-reinforced concrete (FRC) only. The main advantage of synthetic macrofibers over steel is their complete corrosion resistance, which is essential in corrosive environments. Other advantages include their low carbon footprint, reduced construction time, and cost-effectiveness. This paper outlines the optimization process for a conventional cast-in-situ concrete manhole. The imperative for a monolithic construction system stems from the diverse geometries and distinct designs of individual pipe culverts, compounded by the often-challenging accessibility of installation sites. In the optimization phase, synthetic macrofiber reinforcement replaced conventional reinforcing steel bars, using advanced finite element analysis (FEA). The design was not conducted on an equivalent basis, resulting in potential variations in the load-carrying capacity between reinforced concrete (RC) and FRC manholes. Nevertheless, both are deemed suitable for the specified loads. The conventional design method used for RC and the advanced finite element design method used for FRC were scrutinized, taking into account the existing standard environment. Subsequently, a real-scale test was conducted to validate the calculations. Carbon footprint analyses were performed for both the original and proposed solutions, and the results were compared. The solution obtained in this study is unique and pioneering in terms of both the calculation method and the structural design, and the CO2 calculations validate its necessity. © 2024 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Kanagaraj, Balamurali AU - Priyanka, Raja AU - Anand, N. AU - Kiran, Tattukolla AU - Andrushia, A. Diana AU - Lublóy, Éva Eszter TI - A sustainable solution for mitigating environmental corrosion in the construction sector and its socio-economic concern JF - Case Studies in Construction Materials J2 - CASE STUD CONSTR MAT VL - 20 PY - 2024 PG - 20 SN - 2214-5095 DO - 10.1016/j.cscm.2024.e03089 UR - https://m2.mtmt.hu/api/publication/34785836 ID - 34785836 N1 - Department of Civil Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India Department of Electronics and Communication Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India Department of Construction Materials and Technologies, Faculty of Civil Engineering, Budapest University of Technology and Economics, Budapest, 1521, Hungary Export Date: 12 April 2024 Correspondence Address: Anand, N.; Department of Civil Engineering, India; email: nanand@karunya.edu AB - Corrosion in reinforced concrete (RC) structures is a typical occurrence, particularly in coastal locations. Corrosion occurs when steel reinforcement within concrete is exposed to environmental variables such as moisture, oxygen, and chloride ions, resulting in a chemical reaction that deteriorates the steel and degrades the concrete structure's overall function. In order to create effective mitigation techniques, it is critical to evaluate the impact of corrosion on various types of concrete. Chloride ions, often present in marine environments penetrate the concrete cover and reach the steel reinforcement, through pores. The water-cement ratio is a critical factor in concrete mix design. Excess water in the mix can result in the formation of larger and interconnected pores, during the hydration process. Further, improper curing conditions, such as insufficient moisture during the initial stages of hydration, can cause incomplete hydration and the formation of pores. Therefore use of high dense and highly alkaline concrete such as geopolymer concrete (which does not require water curing), can be employed to reduce the impact of corrosion. In the present study an attempt was created to examine the rate of corrosion resistance in three different concrete types: conventional cement concrete (CC), self-compacting concrete (SCC), and geopolymer concrete (GPC). To induce corrosion in the RC (RC) beams, an accelerated corrosion test setup was employed. The main objective of the study is to examine and compare the corrosion resistance of the RC beams by altering the concrete type, which were then exposed to accelerated corrosion to replicate the consequences of long-term exposure to corrosive environments. From the experimental studies it was found that the CC specimens possess a loss (load carrying capacity) of 31.28%, the SCC and GPC specimens possess a loss of 30.08% and 24.95%, respectively. This shows that GPC has higher resistance to salt solution when compared to SCC and CC specimens. Further all the three specimens show similar ductility index (DI), which was found to be in the range between 2.3 and 2.38 with a marginal variation of ± 0.1. GPC shows a 27.41% reduction in carbon emission compared to CC. On the other hand, SCC demonstrates a 12.30% reduction in carbon emission compared to CC. The investigation revealed that the total energy demand for producing 1 m3 of conventional concrete was measured to be 1.88 gigajoules (GJ/m3). On the other hand, the energy demand for the same volume of self-compacting concrete was slightly lower, specifically 1.78 GJ/m3. © 2024 The Authors LA - English DB - MTMT ER - TY - CONF AU - Juhász, Attila TI - Hadtörténelmi és katonai objektumok rekonstruálása térinformatika és távérzékelés segítségével T2 - 17. Építőmérnöki Tudományos Tanácskozás közleményei SN - 9789634493495 PY - 2024 SP - 7 EP - 18 PG - 12 UR - https://m2.mtmt.hu/api/publication/34779013 ID - 34779013 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Füstös, Vivien AU - Baranya, Sándor AU - Kutassy, Emese AU - Tamás, Enikő Anna AU - Erős, Tibor AU - Józsa, János TI - Validating a Two-dimensional Sediment Transport Model on a Large Danubian Floodplain JF - PERIODICA POLYTECHNICA-CIVIL ENGINEERING J2 - PERIOD POLYTECH CIV ENG PY - 2024 PG - 9 SN - 0553-6626 DO - 10.3311/PPci.23796 UR - https://m2.mtmt.hu/api/publication/34775542 ID - 34775542 AB - Considering currently operative European and worldwide regulations, preserving and/or improving the state of remnant alluvial floodplains is a high-priority goal for experts. One of the threats is the decrease of lateral connectivity: due to the erosion in the mainstem riverbed and the sedimentation of the floodplain and its channels, the bed elevation gap slowly increases between the main channel and the side branches and oxbows of the floodplain. Without revitalization measures, this progress predicts severe ecological consequences. As an example, and as a continuation of our earlier work, we considered the Gemenc floodplain forest along the Danube, in Hungary. We set up a two-dimensional coupled hydrodynamic and sediment transport computational model to describe floodplain deposition dynamics. Model validation was carried out with historical data, i.e., two ground elevation sets measured in 1990 and in 2009, respectively. Our aim was 1. to show, how coarse resolution measured data can be used for validating a large-scale model in terms of sediment deposition processes, and 2. to interpret the first results on some areas exposed to strong deposition, after validation. Showing good agreements in three pillars: magnitude of estimation, spatial tendencies and spatial patterns, the model was deemed valid. We were also able to observe a clear gradient, along which areas could be categorized with high, medium and small extent of sediment deposition. With this model, the sediment dynamics in the Gemenc floodplain forest can be assessed, with special attention to the impact analysis of restoration measures to improve lateral connectivity conditions. LA - English DB - MTMT ER -