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Publications - 6515

New dimensions of internal controls in banking after the GFC

Laszlo Vasa Csaba Lentner Pál P. Kolozsi Zoltán Zéman

Publication Name: Economic Annals Xxi

Publication Date: 2019-08-20

Volume: 176

Issue: 3-4

Page Range: 38-48

Description:

The weakness of the control function of governments and central banks was the main regulatory cause of the global financial crisis (GFC) broke out in 2007, but the suboptimal regulatory environment «corrupted» the quality of internal control and audit of banks as well. After the crisis, corporate governance issues appeared in the focus of international organizations. In this paper, we present the relevant international recommendations aimed at improvement of the weak corporate governance practices of the banking sector. Based on the comparison of pre- and post-crisis internal control functionalities which are presented as a meta-analysis and a systematic review of the existing empirical researches, the authors conclude that the stricter guidelines could and can have a positive impact on banks' operations stabilizing through the strengthening of internal control practices.

Open Access: Yes

DOI: 10.21003/ea.V176-04

Two-dimensional compressible flow simulation on emulated digital CNN-UM

Sándor Kocsárdi Zoltán Nagy Árpád Csík Péter Szolgay

Publication Name: Proceedings of the IEEE International Workshop on Cellular Neural Networks and their Applications

Publication Date: 2008-09-23

Volume: Unknown

Issue: Unknown

Page Range: 169-174

Description:

In the area of mechanical, aerospace, chemical and civil engineering the solution of partial differential equations (PDEs) has been one of the most important problems of mathematics for a long time. In this field, one of the most exciting areas is the simulation of fluid flow, which involves for example problems of air, sea and land vehicle motion. In this paper a CNNUM based solver of 2D inviscid, adiabatic, compressible fluids will be presented. The governing equations are solved by using firstand second-order numerical methods. Unfortunately the necessity of the coupled multi-layered computational structure with nonlinear, space-variant templates does not make it possible to utilize the huge computing power of the analog CNN-UM chips. To improve the performance of our solution emulated digital CNN-UM implemented on FPGA has been used. Properties of the implemented specialized architecture is examined in terms of area, speed and accuracy. ©2008 IEEE.

Open Access: Yes

DOI: 10.1109/CNNA.2008.4588672

A novel unified approach to invariance conditions for a linear dynamical system

Yunfei Song Tamás Terlaky Zoltán Horváth

Publication Name: Applied Mathematics and Computation

Publication Date: 2017-04-01

Volume: 298

Issue: Unknown

Page Range: 351-367

Description:

In this paper, we propose a novel, simple, and unified approach to explore sufficient and necessary conditions, i.e., invariance conditions, under which four classic families of convex sets, namely, polyhedra, polyhedral cones, ellipsoids, and Lorenz cones, are invariant sets for a linear discrete or continuous dynamical system. For discrete dynamical systems, we use the Theorems of Alternatives, i.e., Farkas lemma and S-lemma, to obtain simple and general proofs to derive invariance conditions. This novel method establishes a solid connection between optimization theory and dynamical system. Also, using the S-lemma allows us to extend invariance conditions to any set represented by a quadratic inequality. Such sets include nonconvex and unbounded sets. For continuous dynamical systems, we use the forward or backward Euler method to obtain the corresponding discrete dynamical systems while preserves invariance. This enables us to develop a novel and elementary method to derive invariance conditions for continuous dynamical systems by using the ones for the corresponding discrete systems. Finally, some numerical examples are presented to illustrate these invariance conditions.

Open Access: Yes

DOI: 10.1016/j.amc.2016.10.007

Fake News Classification on Social Media in the Field of Environmental Engineering

Ferenc Erdos Katalin Kovács Richard Nemeth

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 961-966

Description:

Environmental engineering plays a crucial role in addressing the sustainability challenges of the environment and everyday life. These areas cover a wide range of aspects, from environmental impacts, efficient use of natural resources, waste management and recycling, and improving air and water quality to preventing, managing and mitigating environmental hazards and disasters. For example, climate change, global warming, pollutant emissions, etc., are frequently discussed on social media. Unfortunately, however, these platforms, as the primary means of mass information, provide scope for misinformation, manipulation and influencing opinions through dubious or outright fake news and posts. Despite the prevalence and growing volume of research on detecting fake news, there is a significant lack of quality publications focusing specifically on this environmental engineering-related area. In this paper, the authors aim to bridge this gap by developing a supervised machine-learning model for detecting fake news in this field of science. To build a robust model, a training dataset was constructed by using a specific dataset of labelled social media posts containing keywords from Chemical Engineering Transactions journal articles, with a particular focus on sustainability and environmental aspects. This research contributes to enhancing the integrity of environmental engineering in social media discourse by providing a tool for identifying and mitigating the spread of misinformation, promoting informed decision-making and critical thinking, and improving public awareness of environmental matters.

Open Access: Yes

DOI: 10.3303/CET24114161

Feedback linearization with integrator of DCDC buck converter taking into account parasitic elements

Miklós Kuczmann Miklos CSIZMADIA

Publication Name: Proceedings 2021 IEEE 19th International Power Electronics and Motion Control Conference Pemc 2021

Publication Date: 2021-04-25

Volume: Unknown

Issue: Unknown

Page Range: 97-101

Description:

This paper presents the feedback linearization based control of DC/DC buck converter, the output voltage controlled. Also, the presence of parasitic elements are not studied in detail in a previous article, therefore the applied state space model are taking into account of those. The high slew rate of the controller cause inrush current during start-up, which have been examined and reduced. The linearized system has been investigated with linear quadratic regulator (LQR) through an example and simulated via Matlab.

Open Access: Yes

DOI: 10.1109/PEMC48073.2021.9432632

Family friendly concepts and tools in different-sized Hungarian organizations based on empirical study

Andrea Bencsik Timea Juhasz

Publication Name: Problems and Perspectives in Management

Publication Date: 2010-01-01

Volume: 8

Issue: 1

Page Range: 70-79

Description:

In today's world, more and more people have been thinking whether to put their family or their career to the foreground as there does not seem to exist any balance between the two aspects today. The reconciliation of work and family life can be seen today not only as an individual, but rather, as an organizational problem. After all, an employee who is tense, exhausted or tired because of his/her responsibilities at home will not be effective at work and vice versa. It is no wonder, then, that several Hungarian organizations are putting more and more emphasis on solving these occasional problems. In this article, an empirical survey is used to present the different tools used by different-sized Hungarian companies to help employees reconcile their work and their private lives. © Habil Andrea Bencsik, Tímea Juhász, 2010.

Open Access: Yes

DOI: DOI not available

The Effect of Lubricant Viscosity Variation on Tooth Friction and Hence on the Energetic Behaviour of Gear Unit

József Polák

Publication Name: Chemical Engineering Transactions

Publication Date: 2024-01-01

Volume: 114

Issue: Unknown

Page Range: 853-858

Description:

Earlier this year, I created a mathematical model of a gear unit that allowed me to investigate the energy performance of a vehicle gear unit over its full operating range. In the model created, the value of the tooth friction was determined during a precalculation and then entered into the model as a constant parameter. The problem with this approach is that it is not automated, so during the energy analysis or a possible optimisation of the gear unit, the tooth friction is always present in the model as a constant value, whereas in reality, the value of the tooth friction is different for different working points (wheel torque: Mw, wheel speed: nw) and different geometries. The viscosity of the selected lubricant has a significant influence on tooth friction, which varies partly due to temperature and partly due to load. In this paper, I will investigate the viscosity of the oil required by the gear unit at different operating points for proper operation and how this affects tooth friction and, hence, the gear unit energy loss. Since the studies showed that the effect of oil viscosity is not significant but not negligible, the determination of tooth friction can be incorporated into the gear unit model using a MATLAB function so that it is re-determined at each operating point and for each geometry change. With this modification, the estimation generated by the mathematical model describing the energetic behavior of the gear unit can be made more accurate.

Open Access: Yes

DOI: 10.3303/CET24114143

Fuzzy and Kohonen SOM based classification of different 0D nanostructures

Márk Farkas Ákos Nemcsics Antal Ürmös Zoltán Farkas Tamás Sándor Laszlo T. Koczy

Publication Name: Sami 2017 IEEE 15th International Symposium on Applied Machine Intelligence and Informatics Proceedings

Publication Date: 2017-03-16

Volume: Unknown

Issue: Unknown

Page Range: 365-370

Description:

In this paper, the clustering of the GaAs-based droplet epitaxially grown self-assembled nanostructures was investigated by soft-computing methods. The properties and the operation of these devices, depend on the type, the shape, the size, and their distribution of these 0 dimensional nanostructures. Because of this, it is very important to know, how and what kind of nanostructures can form, at the given technological parameters. Our goal is the classification of these nanostructures, in order to support the research and the production of these devices. Our solution is based on the shape factor calculation of the given nanostructure. In this work, two possible classification methods of nanostructures were introduced as well. First, the classification potential of the Kohonen Self-Organizing Mapping (SOM) was investigated. Second, the fuzzy inference system based classification was studied. In this case, the shape factor was determined by geometrical sizes of the nanostructures. In this paper the clustering was introduced, which supports many kinds of technology as well.

Open Access: Yes

DOI: 10.1109/SAMI.2017.7880335

Experimental results of sliding and welding tests in a novel construction method for steel-concrete composite bridges

János Szép Daniel Gosztola

Publication Name: Fib Symposium

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 923-930

Description:

The primary objective of this study is to introduce a novel construction method used for steel-concrete composite bridges. Throughout the article, domestic and international solutions and practices will be provided for various girder-prefabricated deck slab connections, as well as construction methods for steel-concrete composite bridges. The new bridge construction technology involves the construction of a prefabricated deck slab on-site, which is moved into its final position on the main girders. During prefabrication, a stud plate is positioned within the formwork, facilitating the sliding of the deck slab elements onto the girder. The upper flange and stud plate are joined by welding following the sliding of the deck parts. The key challenge for this technology is achieving a sufficiently low friction coefficient between the stud plate and the flange using a suitable material. However, it is imperative to identify a material that can be compatible with the welded connection. Laboratory experiments were carried out to investigate the effect of materials on the friction coefficients between steel plates and the welding of the connection. The ideal material has been identified through experiments to lower the coefficient of friction to 4-8% while the welded joint can be achieved.

Open Access: Yes

DOI: DOI not available