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Found 6414 publications

Combustion and Emission Analyses of a Diesel Engine Running on Blends with Methanol

Justas Žaglinskis Kristóf Lukács György Szabados Ákos Bereczky

Publication Name: Energy Environment and Sustainability

Publication Date: 2021-01-01

Volume: Unknown

Issue: Unknown

Page Range: 141-172

Description:

The ambient air around us is continuously and increasingly loaded and polluted through emission that comes from different sectors, especially from the transportation sector. This fact is due to the growing energy consumption in the transport sector which is forecasted worldwide in the nearer and far future. Bio-based energy may be consumed in an increasing way in the sector until 2050. Methanol, and if it is produced on bio-basis, called bio-methanol, is the simplest alcohol. Methanol costs less than other automotive alternative alcohols, for example, ethanol or butanol, so it may be among the cheapest technical alcohols. As for methanol’s structure, it contains 30% more inherent oxygen on a molecular base than fossil diesel. The aim of this research is to give comprehensive overview about the methanol’s effect on the combustion and emission properties of a diesel engine. During the analyses of combustion and emission characteristics the most relevant parameters have been included. The study also contains calculations regarding theoretical combustion (oxidation process) of the different hydrogen-carbons. A rarely investigated parameter, O2 consumption or demand is also in focus, besides CO2 emission and intensity throughout the calculations. For our experimental test series, diesel fuel was the base fuel and it has been mixed with biodiesel first, and this mixture has been further blended with methanol. Methanol’s theoretical contribution to the diesel–biodiesel blend’s O2 consumption and CO2 emission is a small amount. Engine’s external parameters have not changed significantly if it is running on blend with methanol. Methanol has rather affected the combustion and emission properties of the engine more significantly.

Open Access: Yes

DOI: 10.1007/978-981-16-1280-0_6

Hungarian migrant communities decoupling from the old country in the United States -s

Balázs Pálvölgyi

Publication Name: Diasporas

Publication Date: 2018-01-01

Volume: Unknown

Issue: 31

Page Range: 51-64

Description:

No description provided

Open Access: Yes

DOI: 10.4000/diasporas.1113

Improved behavioral analysis of fuzzy cognitive map models

Miklós F. Hatwágner Gyula Vastag Laszlo T. Koczy Vesa A. Niskanen

Publication Name: Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics

Publication Date: 2018-01-01

Volume: 10842 LNAI

Issue: Unknown

Page Range: 630-641

Description:

Fuzzy Cognitive Maps (FCMs) are widely applied for describing the major components of complex systems and their interconnections. The popularity of FCMs is mostly based on their simple system representation, easy model creation and usage, and its decision support capabilities. The preferable way of model construction is based on historical, measured data of the investigated system and a suitable learning technique. Such data are not always available, however. In these cases experts have to define the strength and direction of causal connections among the components of the system, and their decisions are unavoidably affected by more or less subjective elements. Unfortunately, even a small change in the estimated strength may lead to significantly different simulation outcome, which could pose significant decision risks. Therefore, the preliminary exploration of model ‘sensitivity’ to subtle weight modifications is very important to decision makers. This way their attention can be attracted to possible problems. This paper deals with the advanced version of a behavioral analysis. Based on the experiences of the authors, their method is further improved to generate more life-like, slightly modified model versions based on the original one suggested by experts. The details of the method is described, its application and the results are presented by an example of a banking application. The combination of Pareto-fronts and Bacterial Evolutionary Algorithm is a novelty of the approach.

Open Access: Yes

DOI: 10.1007/978-3-319-91262-2_55

Analysis Of The Dynamics Of Cashless Payments In Kazakhstan In The Context Of The Covid-19 Pandemic

Laszlo Vasa Anna Kredina Aigul Akparova

Publication Name: Economy Strategy and Practice

Publication Date: 2021-01-01

Volume: 16

Issue: 2

Page Range: 54-61

Description:

The COVID-19 pandemic has accelerated the development of FinTech and the transition to cashless payments of the population of various countries, including Kazakhstan. For provision of cashless payments there are created platforms which work in NFC & MFS systems, they protected by security protocols (Secure Element (SE)) and allow to store confidential user data. Changes in the business model of banks have led to the emergence of a new format of banking products and services that can be used through smartphones (the main operating systems Android and iOS). The goal of the study is to analyze the dynamics of the impact of the COVID-19 pandemic on the use of cashless payments through national payment systems in Kazakhstan. Based on the goal, a null and an alternative hypothesis were set, of which the second was confirmed in the result. Research methods used to write this article are economic and statistical analysis and synthesis, graphical method, analysis of the series of dynamics. The data for the study was taken from the NBK Statistical Bulletin: data on cashless payments through the Interbank System of Money Transfer (ISMT) and the Interbank Clearing System (ICS) for the period from 2002 to 2020. The impact of the COVID-19 pandemic on the dynamics of the transformation of cashless payments made by using financial technologies has been proved. Recommendations for further improvement of the financial system are given. The development of national payment systems makes it possible to reduce the level of fraud in the financial sector, to increase the speed of cashless transfers and level out transaction errors. Study limitation: only national payment systems ISMT and ICS were used.

Open Access: Yes

DOI: 10.51176/1997-9967-2021-2-54-61

Linear fuzzy rule base interpolation using fuzzy geometry

Suman Das Laszlo T. Koczy Debjani Chakraborty

Publication Name: International Journal of Approximate Reasoning

Publication Date: 2019-09-01

Volume: 112

Issue: Unknown

Page Range: 105-118

Description:

Fuzzy Rule Interpolation (FRI) provides an interpretable decision in sparse fuzzy rule based system. The objective of this work is to establish a mathematical demonstration of the pattern of existing fuzzy rule base using fuzzy geometry. Though several authors contributed on fuzzy rule base interpolation but there is a need to generate closed mathematical form of interpolating pattern. The present work is an initiative to demonstrate the same. First part of this paper presents some spatial geometrical transformation of a fuzzy point. In the second part of this paper, a new FRI scheme is suggested using fuzzy geometry with above mentioned transformation. The proposed method operates in two different steps. In the first step, all the fuzzy rules are converted into fuzzy sets or mostly fuzzy points in higher dimension by using mathematical operator on the individual of antecedent and consequent parts. All rules or fuzzy points are then joined with a class of fuzzy line segments (FLS). Second step considers the identification of mathematical pattern of the interpolated piecewise linear fuzzy polynomial which is able to compute the desired conclusion of a given observation. The presented method not only associates the FRI technique to classical interpolation technique, but also promises to provide the geometrical visualization of the behaviour of fuzzy sets during the interpolation process.

Open Access: Yes

DOI: 10.1016/j.ijar.2019.05.004

Europeanization of the Hungarian legal order: From convergence to cancellation?

Balázs Horváthy Tamas Dezso Ziegler

Publication Name: Law in Eastern Europe

Publication Date: 2018-01-01

Volume: 67

Issue: Unknown

Page Range: 24-40

Description:

Since the political transition of Hungary in the late 1980s, the law of the European Union has been the primary external influence on the modernization of domestic legislation. This chapter aims to illustrate that Hungary, as a passive and receptive actor, implemented all components of eu law which were prerequisites for eu membership. This has resulted in an intense convergence in rules and values of the domestic and eu legal order until its accession to the eu in 2004. After accession, however, Hungary started to move from a constructive to confrontational Member State, which has led to a substantial divergence between the laws of Hungary and eu law. This chapter analyzes these processes and attempts to identify the possible consequences of this alteration in the Hungarian stance to the adoption of rules, values, and regulatory models originating from eu law. It will be demonstrated with case studies ranging from recent Hungarian economic legislation to the constitutional reform, illustrating how this new role of Hungary negatively affects the adaptability of Hungarian legal order and leads to canceling the convergence to the European law.

Open Access: Yes

DOI: 10.1163/9789004352070_004

How to design a dynamically-feasible heat exchanger network? Insights gained from experience

Hao Yeh Lee Ákos Orosz Bing Shen How Zong Yang Kong Tiffany Ang Ferenc Friedler

Publication Name: Energy

Publication Date: 2026-02-01

Volume: 344

Issue: Unknown

Page Range: Unknown

Description:

This paper aims to share the challenges encountered by the authors while exploring the significance of controllability in the early stage of heat exchanger network (HEN) design, particularly through the use of P-HENS – a graph theoretic-based HEN synthesis tool for multi-solution HEN synthesis. Presently, no existing studies have leveraged P-HENS-derived networks to reveal insight on how network topology affects its dynamic performance. This work began with a 5-stream problem as a base case, where P-HENS was used to generate four feasible HENs that meets the minimum energy requirement (MER). A preliminary screening narrowed these options to two configurations, which were then simulated in Aspen Plus. Bypass are added to the two selected HENs for further control studies in Aspen Plus Dynamics. The results indicated that both HENs could handle only some disturbances and return the outlet temperature to its nominal value, with some cases showing marginal deviations. Then, different bypass values (e.g., 0.1 and 0.5) were explored to analyze its impact on control performance but it reveals that even with a larger bypass value of 0.5, the HEN struggled to adequately adjust during disturbances. The findings from this work showed that the controllability of the HEN is collectively influenced by the bypass value, the temperature difference of the “direct inlet and outlet of the heat exchanger”, and the temperature difference of the “inlet streams of both hot and cold streams placed in the heat exchanger”. A generic workflow that would help future researchers avoid similar pitfalls has been presented.

Open Access: Yes

DOI: 10.1016/j.energy.2026.139903

Prevalence and Characteristics of Traffic Accidents Endangering Vulnerable Pedestrians in Hungary †

István Lakatos Emese Sánta Gábor Patocskai Petra Szűcs

Publication Name: Engineering Proceedings

Publication Date: 2024-01-01

Volume: 79

Issue: 1

Page Range: Unknown

Description:

In Hungary, around 14,000 to 15,000 traffic accidents result in personal injuries on public roads annually. Half of the individuals involved in fatal collisions are considered vulnerable pedestrians or cyclists. Our retrospective cross-sectional study reviewed the police and medical aspects of personal injury traffic accidents in our county. In 2023, there were 26 fatal accidents, 9 of which involved pedestrians, with 8 being at-fault pedestrians. Additionally, 920 traffic accident patients visited the emergency care department of the county hospital, with 68% of them having injuries that healed within 8 days.

Open Access: Yes

DOI: 10.3390/engproc2024079094

Testing and Modeling Procedure of the 18650 Lithium Battery at Different Temperatures

Adrienn Dineva István Lakatos Szabolcs Kocsis Szurke

Publication Name: 2022 22nd International Symposium on Electrical Apparatus and Technologies Siela 2022 Proceedings

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In this paper a two-time constant (TTC) electrical model is investigated to simulate the operation of 18650 batteries at different temperatures. To determine the parameters of the model, a new test procedure is developed, which can be used to obtain a wide range of information on the behavior of the tested batteries after 10 measurements. After performing the tests, detailed information on the constant, transient, and dynamic behavior of the battery over a wide temperature range is available. After, a statistics-based Ordered Weighted Averaging (OWA) aggregation operator is applied to evaluate the results. The general model is developed based on standardized parameters. Worldwide Harmonized Light Vehicle Test Procedure (WLTP) tests are performed to validate the simulation results. The operation of the model has been tested at 4 different temperatures: -15 °C, 0 °C, 25 °C, 60 °C. The simulation results are compared and evaluated with real measurement data.

Open Access: Yes

DOI: 10.1109/SIELA54794.2022.9845767