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Found 6423 publications
Financial Innovations for the Sustainable Development of Smart City Infrastructure
Publication Name: World Sustainability Series
Publication Date: 2026-01-01
Volume: Part F1269
Issue: Unknown
Page Range: 31-53
Description:
The transition towards smart cities necessitates innovative and sustainable financial models that integrate technological advancements with long-term economic viability. This study explores the role of financial innovations, including blockchain-based funding, green bonds, and decentralized finance (DeFi), in supporting the sustainable growth of urban infrastructure. Traditional financing mechanisms often struggle to accommodate the rapid evolution of smart city initiatives, making innovative financial instruments essential for ensuring both economic and environmental sustainability. The research is based on a comprehensive literature review and case studies from leading smart cities such as Singapore, Amsterdam, Barcelona, and New York. Blockchain technology facilitates transparent and automated financing through smart contracts, while green bonds and other ESG-focused instruments enhance private sector participation in sustainable urban projects. Crowdfunding and tokenization further enable community-driven investments in smart infrastructure, strengthening citizen engagement and financial inclusivity. After analyzing these innovative financial instruments, the paper aims to propose a simple model to help identify which instrument is best suited to a city’s transition, considering its specific geographical, social, and economic context.
Open Access: Yes
Investigation of the Causes of Railway Track Gauge Narrowing
Publication Name: Vehicles
Publication Date: 2023-09-01
Volume: 5
Issue: 3
Page Range: 949-977
Description:
On behalf of MÁV Hungarian State Railways Ltd., the authors carried out a research and development (R&D) project on behalf of the Budapest University of Technology and Economics, Department of Highway and Railway Engineering, on the subject of “Research and investigation of the causes of gauge narrowing by finite-element modeling in running track and turnout, and under operational and laboratory conditions”. The main objective of the research was to investigate the causes of localized defects of gauge narrowing in railway tracks based on machine and manual track measurements, laboratory measurements, and theoretical considerations. The measures proposed as a consequence of identifying the causes could significantly contribute to reducing the number and extent of local defects in the future. Furthermore, the research aims to develop new theories in less scientifically mature areas and provide procedures and instructions that professional engineers and practitioners can easily apply. The main areas of research, which are not exhaustive, are as follows: (i) the evaluation of the measurement results provided by track geometry measuring and recording cars; (ii) on-site investigations in the railway track in terms of gauge and rail profile measurements; and, based on these, (iii) the selection of concrete sleepers, which were removed from the track and subjected to more detailed geometrical investigations in the laboratory, together with the components of the rail reinforcement; (iv) the track–vehicle connection, tight running in straight and curved track sections under track confinement; (v) modeling of the stability and deflection of the rail when the rail fastenings lose part of their supporting function; and (vi) finite element modeling of the concrete sleepers under operating conditions such as slow deformation of the concrete, temperature variation effects, and lateral support on the ballast. In the already-narrowed track section, the tight vehicle running is not the cause of the track gauge narrowing but a consequence, so it is not investigated in this paper.
Open Access: Yes
Influence of microbial inoculants on co-composting of lignocellulosic crop residues with farm animal manure: A review
Publication Name: Journal of Environmental Management
Publication Date: 2022-01-15
Volume: 302
Issue: Unknown
Page Range: Unknown
Description:
The rapidly developing agro-industry generates huge amounts of lignocellulosic crop residues and animal manure worldwide. Although co-composting represents a promising and cost-effective method to treat various agricultural wastes simultaneously, poor composting efficiency prolongs total completion time and deteriorates the quality of the final product. However, supplementation of the feedstock with beneficial microorganisms can mitigate these negative effects by facilitating the decomposition of recalcitrant materials, enhancing microbial enzyme activity, and promoting maturation and humus formation during the composting process. Nevertheless, the influence of microbial inoculation may vary greatly depending on certain factors, such as start-up parameters, structure of the feedstock, time of inoculation, and composition of the microbial cultures used. The purpose of this contribution is to review recent developments in co-composting procedures involving different lignocellulosic crop residues and farm animal manure combined with microbial inoculation strategies. To evaluate the effectiveness of microbial additives, the results reported in a large number of peer-reviewed articles were compared in terms of composting process parameters (i.e., temperature, microbial activity, total organic carbon and nitrogen contents, decomposition rate of lignocellulose fractions, etc.) and compost characteristics (humification, C/N ratio, macronutrient content, and germination index). Most studies confirmed that the use of microbial amendments in the co-composting process is an efficient way to facilitate biodegradation and improve the sustainable management of agricultural wastes. Overall, this review paper provides insights into various inoculation techniques, identifies the limitations and current challenges of co-composting, especially with microbial inoculation, and recommends areas for further research in this field.
Open Access: Yes
Optimization-based parameter tuning of unscented Kalman filter for speed sensorless state estimation of induction machines
Publication Name: Proceedings 2017 5th International Symposium on Electrical and Electronics Engineering Iseee 2017
Publication Date: 2017-12-07
Volume: 2017-December
Issue: Unknown
Page Range: 1-7
Description:
State estimation of induction machines may be a difficult problem, due to the non-linear behavior of theirs. For non-linear state estimation, the unscented Kalman filter (UKF) is a well-known extension of the linear Kalman filter. Operation of the UKF algorithm strongly depends on the process and measurement noise covariance parameters of the estimator. Determination of these parameters is not straightforward and can be difficult, especially if the number of state variables and hence the system complexity is relatively high. In this paper, the UKF algorithm is applied for speed sensorless state estimation of induction machines in such a way that seven state variables are estimated from the measured stator currents and from the known excitation voltages. In order to tune the noise parameters of the UKF, a new, optimization-based method is presented. This tuning method provides adequate behavior for the observer beside difficult operating conditions as it has been shown by simulation experiment.
Open Access: Yes
Regenerative Braking Optimization of Lightweight Vehicle based on Vehicle Model
Publication Name: Chemical Engineering Transactions
Publication Date: 2022-01-01
Volume: 94
Issue: Unknown
Page Range: 601-606
Description:
The usage of regenerative braking highly improves the overall energy efficiency of electric vehicles. In this paper, the model-based optimization of the torque profile is determined in the regenerative braking process of a lightweight electric vehicle. For the optimization, measurement-based vehicle model was used, where the extended powertrain model was set up, including the regenerative operation. The whole model was elaborated in MATLAB Simulink environment, where genetic algorithm (GA) was applied for the optimization. The resulted optimized braking curve was applied to control the experimental vehicle and field test were made to validate the optimization results. The results of the presented work can be directly used to further improve the drive cycle efficiency of the urban electric vehicles. The application of optimized driving strategies, including regenerative braking, could contribute to further energy and pollution reduction in urban transportation.
Open Access: Yes
DOI: 10.3303/CET2294100
Experimental Investigation of the Friction Modifying Effects of Different Nanoforms of Graphene Additives in Engine Lubricating Oil
Publication Name: Fme Transactions
Publication Date: 2022-01-01
Volume: 50
Issue: 2
Page Range: 248-259
Description:
This article presents the results of an experimental investigation of different nanoforms of graphene used as a nano additive in engine lubricating oil. The experiments were carried out on a pin-on-disc tribometer at the Department of Internal Combustion Engines and Propulsions at Széchenyi István University. The paper introduces the experimental equipment and the experimental method and presents the research findings. The paper concludes that fullerene can decrease friction by 7% on average when used as a nano additive in engine lubricating oil. Furthermore, fullerene did not present a sedimentation problem when used as an additive up to 0.25 wt% in lubricant instead of graphene and multiwalled carbon nanotubes. The paper attempts to explain the friction decreasing effect and the possible roles of carbon nano additives in tribological systems.
Open Access: Yes
DOI: 10.5937/fme2201248T
Progress in diagnostics of the COMPASS tokamak
V. Weinzettl
M. Peterka
A. Podolnik
J. Seidl
R. Paprok
P. Vondráček
M. Stano
T. Krizsanoczi
M. Dimitrova
P. Bilková
N. Vianello
M. Sos
J. Varju
M. Tomes
M. Varavin
M. Hron
J. Zajac
F. Zacek
M. Berta
T. Markovic
A. Devitre
M. Komm
O. Grover
P. Háček
E. Gauthier
E. Matveeva
J. Mlynar
D. Naydenkova
K. Kovarik
M. Rabinski
J. Adamek
J. Stöckel
J. Horacek
R. Pánek
R. Dejarnac
J. Havlicek
A. Havranek
R. Gomes
M. Vlainic
A. Silva
S. Zoletnik
P. Böhm
J. Cavalier
O. Ficker
M. Imrišek
G. Anda
D. Dunai
D. Refy
T. Pereira
Tsv Popov
D. Sarychev
G. P. Ermak
J. Zebrowski
M. Jakubowski
J. Krbec
S. Nanobashvili
M. Spolaore
O. Bogár
K. Mitošinková
K. Malinowski
D. Fridrich
J. P. Gunn
Publication Name: Journal of Instrumentation
Publication Date: 2017-12-07
Volume: 12
Issue: 12
Page Range: Unknown
Description:
The COMPASS tokamak at IPP Prague is a small-size device with an ITER-relevant plasma geometry and operating in both the Ohmic as well as neutral beam assisted H-modes since 2012. A basic set of diagnostics installed at the beginning of the COMPASS operation has been gradually broadened in type of diagnostics, extended in number of detectors and collected channels and improved by an increased data acquisition speed. In recent years, a significant progress in diagnostic development has been motivated by the improved COMPASS plasma performance and broadening of its scientific programme (L-H transition and pedestal scaling studies, magnetic perturbations, runaway electron control and mitigation, plasma-surface interaction and corresponding heat fluxes, Alfvenic and edge localized mode observations, disruptions, etc.). In this contribution, we describe major upgrades of a broad spectrum of the COMPASS diagnostics and discuss their potential for physical studies. In particular, scrape-off layer plasma diagnostics will be represented by a new concept for microsecond electron temperature and heat flux measurements - we introduce a new set of divertor Langmuir and ball-pen probe arrays, newly constructed probe heads for reciprocating manipulators as well as several types of standalone probes. Among optical tools, an upgraded high-resolution edge Thomson scattering diagnostic for pedestal studies and a set of new visible light and infrared (plasma-surface interaction investigations) cameras will be described. Particle and beam diagnostics will be covered by a neutral particle analyzer, diagnostics on a lithium beam, Cherenkov detectors (for a direct detection of runaway electrons) and neutron detectors. We also present new modifications of the microwave reflectometer for fast edge density profile measurements.
Open Access: Yes
Humanitarian Drones: A Review and Research Agenda
Publication Name: Internet of Things Netherlands
Publication Date: 2021-12-01
Volume: 16
Issue: Unknown
Page Range: Unknown
Description:
This study investigates the capabilities, performance outcomes, and barriers of drones applied to humanitarian logistics (HL). A systematic literature review was conducted to synthesize prior research on drones and cumulatively identify current knowledge gaps which require further investigation. In order to identify the relevant literature on the topic, a rigorous research protocol was applied for the retrieval and selection processes. In total, 142 publications fulfilled the selection criteria and were thoroughly analyzed. The findings of this review paper summarize the capabilities, barriers and performance outcomes of humanitarian drones applied to logistics operations, management, and governance in a comprehensive framework. More specifically, three important capabilities (i.e., transportation and delivery; surveying and monitoring; communication and integration), three performance outcomes (i.e., flexibility and responsiveness; cost reduction; sustainability) and adoption barriers in three areas (i.e., technology; organization; environment) were identified. Based on these findings, future research directions are derived for the capabilities of humanitarian drones, their performance outcomes, and their respective barriers. This study analyzes potential applications of drones in the humanitarian field and presents a comprehensive agenda that structures and guides further research on the topic.
Open Access: Yes
Numerical Investigation of Pre-Stressed Reinforced Concrete Railway Sleeper for High-Speed Application
Publication Name: Infrastructures
Publication Date: 2023-03-01
Volume: 8
Issue: 3
Page Range: Unknown
Description:
The current paper deals with the numerical investigation of a unique designed pre-stressed reinforced concrete railway sleeper for the design speed of 300 km/h, as well as an axle load of 180 kN. The authors applied different methodologies in their research: traditional hand-made calculations and two types of finite element software. The latter were AxisVM and ABAQUS, respectively. During the calculations, the prestressing loss was not considered. The results from the three methods were compared with each other. The hand-made calculations and the finite element modeling executed by AxisVM software are adequate for determining the mechanical inner forces of the sleeper; however, ABAQUS is appropriate for consideration of enhanced and sophisticated material models, as well as the stress-state of the elements, i.e., concrete, pre-stressed tendons, etc. The authors certified the applicability of these methodologies for performing the dimensioning and design of reinforced concrete railway sleepers with pre-stressing technology. The research team would like to continue their research in an improved manner, taking into consideration real laboratory tests and validating the results from FE modeling, special material models that allow calculation of crackings and their effects in the concrete, and so that the real pattern of the crackings can be measured by GOM Digital Image Correlation (DIC) technology, etc.
Open Access: Yes
