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On the Convergence of Input-Output Fuzzy Cognitive Maps

István A. Harmati Ĺaszĺo T. Ḱoczy

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

Publication Date: 2020-01-01

Volume: 12179 LNAI

Issue: Unknown

Page Range: 449-461

Description:

Fuzzy cognitive maps are recurrent neural networks, where the neurons have a well-defined meaning. In certain models, some neurons receive outer input, while other neurons produce the output of the system. According to this observation, some neurons are categorized as input neurons and the others are the state neurons and output neurons. The output of the system is provided as a limit of an iteration process, which may converge to an equilibrium point, but limit cycles or chaotic behaviour may also show up. In this paper, we examine the existence and uniqueness of fixed points for two types of input-output fuzzy cognitive maps. Moreover, we use network-based measures like in-degree, out-degree and connectivity, to express conditions for the convergence of the iteration process.

Open Access: Yes

DOI: 10.1007/978-3-030-52705-1_33

Numerical plastic analysis of non-prismatic reinforced concrete beams strengthened by carbon fiber reinforced polymers

No authors available

Publication Name: fib Symposium

Publication Date: 2020-01-01

Volume:

Issue:

Page Range: 208-215

Description:

The non-prismatic reinforced concrete (RC) beam considered a unique case in structural engineering as it has variable depth all over beam section and it doesn’t have sufficient information in structural codes, this can put structural engineers in a challenge to predict how this beam will react under specific types of loads or with different geometrical variables and strengthening existence. In this research, concrete plastic damage constitutive model developed and used to explore the shear strength of non-prismatic RC beam structure. Furthermore, in order to improve the shear strength of existent RC beams, Carbon Fiber Reinforced Polymers (CFRP) strips are attached to the surface of the critical sections. For this aim, initially numerical model was calibrated according to the data obtained from laboratory tests then a series of numerical simulations with different variables are carried out to investigate the shear behavior and these variables were: haunch angle α value and CFRP strips existence (composite status). The numerical results show that changing beams geometry (haunch angle α value) can have an influence over shear strength, in addition, using CFRP strips has an obvious effect on the failure behavior of the non-prismatic RC beam structure. Finite element simulations are executed by using ABAQUS.

Open Access: No

DOI: DOI not available

Innovative solutions in the development of households’ financial awareness: A hungarian example

Laszlo Vasa Csaba Lentner Sági Judit

Publication Name: Economics and Sociology

Publication Date: 2020-01-01

Volume: 13

Issue: 3

Page Range: 27-45

Description:

Financial crises put stress on the society of the country of our investigation, whose financial vulnerability is raising from high indebtedness, a history of defaulted loans, and an insufficient level of financial literacy. In this context, financial awareness has been recognised as a means for decreasing households’ exposure to financial difficulties, bridging crisis periods with the substantial precautionary holding of liquid assets, and improving their well-being over longer periods of time. Raising financial awareness is a crucial policy aim, and has been investigated in this study as well. A questionnaire survey was completed by Hungarian university students across different majors, to assess the financial literacy level of the responders from their own perspective. In addition to this, we have investigated their e-banking habits. According to our findings, different student groups (clusters) have been identified by means of Ward analysis (where the significance of clusters were tested by ANOVA). Our results confirm that across all clusters the university students place their trust in non-governmental organisations and central bank foundations rather than those of the financial institutions in evolving financial literacy. This outcome of our study may provide an argument for designing policy incentives for raising financial awareness in an institutionalised way, relying on the role of the privately funded NGOs and on the central bank.

Open Access: Yes

DOI: 10.14254/2071-789X.2020/13-3/2

A new assessment methodology for fair-faced concrete surfaces based on digital image processing

No authors available

Publication Name: fib Symposium

Publication Date: 2020-01-01

Volume:

Issue:

Page Range: 288-295

Description:

Fair-faced concrete elements have become even more popular in architecture because of their pure aesthetics and favourable material properties. The europian standards and guidelines are usually specifying four classes regarding to the surface quality. However, the strandard assessment methodologies are based only on manual methods and they are very subjective in some cases. In order to increase the efficiency and accuary of the evaluation a new methodology is proposed using digital image processing. In this paper the basis of the evaluation method made by using the Python 3.6 software is presented by focusing on the surface void ratio which is one of the most common surface defects of fair-faced concrete structures.

Open Access: No

DOI: DOI not available

Quasi-Optimization of the Time Dependent Traveling Salesman Problem by Intuitionistic Fuzzy Model and Memetic Algorithm

Peter Foldesi Boldizsar Tuu-Szabo Ruba Almahasneh Ĺaszĺo T. Ḱoczy

Publication Name: Studies in Computational Intelligence

Publication Date: 2020-01-01

Volume: 872

Issue: Unknown

Page Range: 239-253

Description:

The Traveling Salesman Problem (TSP) is an NP-hard graph search problem. Despite having numerous modifications of the original abstract problem, Time Dependent Traveling Salesman Problem (TD TSP) was one of the most realistic extensions under real traffic conditions. In TD TSP the edges between nodes are assigned higher costs (weights), if they were traveled during the rush hour periods, or crossed the traffic jam regions, such as the city center(s). In this paper we introduce an even more real-life motivated approach, the Intuitionistic Fuzzy Time Dependent Traveling Salesman Problem (IFTD TSP), which is a further extension of the TSP, and also of the classic TD TSP, with the additional notion of using intuitionistic fuzzy sets for the definition of uncertain costs, time, and space of the rush hour—traffic jam region affecting graph sections. In IFTD TSP we use fuzzy memberships and non-memberships sets for estimating the vague costs between nodes in order to quantify the behavior of traffic jam regions, and the rush hour periods. Since intuitionistic fuzzy sets are generalizations of classic fuzzy sets, our approach may be considered an extension and substitution of the original abstract TD TSP problem, even, of the (classic) Fuzzy TD TSP. Lastly, DBMEA (Discrete Bacterial Memetic Evolutionary Algorithm) was applied on the IFTD TSP model, the results of the simulation runs based on some extensions of the benchmarks generated from the original TD TSP data set showed quite good and promising preliminary results.

Open Access: Yes

DOI: 10.1007/978-3-030-34409-2_14

Applying fuzzy hough transform for identifying honed microgeometrical surfaces

Brigita Sziová Levente Solecki Balázs Sarkadi-Nagy Ĺaszĺo T. Ḱoczy Szilvia Nagy

Publication Name: Studies in Computational Intelligence

Publication Date: 2020-01-01

Volume: 819

Issue: Unknown

Page Range: 35-42

Description:

In the measurement of microgeometrical surfaces it is useful if the same location can be found on a surface for two or more different and independent measurements, as in this case not only statistical parameters of the measurements can be compared, but direct differences can be calculated. Honing is a typical surface processing method resulting in pattern consisting of straight valleys crossing at various angles. Honing pattern is of great help to find a special location. The main goal of this article is to find a method that is able to give some characteristic points that can be used for fitting two measured surfaces together. Hough transform is used in finding straight lines in an image or map, thus it could be used for determining crossing points of the honed surface. However, classical Hough transform either finds way too many disturbing lines in the case of a typical honed surface or almost none, depending on the parameter selection. To solve this rapid changing in the number of the resulting lines, we introduced fuzzy Hough transform. If a fuzzified version of the weights of the individual points in the Hough transform is used, the inverse of the transform becomes clearer, resulting in a pattern more suitable for finding the same location on two measured versions of a surface.

Open Access: Yes

DOI: 10.1007/978-3-030-16024-1_5

On wavelet based enhancing possibilities of fuzzy classification methods

Ferenc Lilik Brigita Sziová Levente Solecki Ĺaszĺo T. Ḱoczy Szilvia Nagy

Publication Name: Advances in Intelligent Systems and Computing

Publication Date: 2020-01-01

Volume: 945

Issue: Unknown

Page Range: 56-73

Description:

If the antecedents of a fuzzy classification method are derived from pictures or measured data, it might have too many dimensions to handle. A classification scheme based on such data has to apply a careful selection or processing of the measured results: either a sampling, re-sampling is necessary or the usage of functions, transformations that reduce the long, high dimensional observed data vector or matrix into a single point or to a low number of points. Wavelet analysis can be useful in such cases in two ways. As the number of resulting points of the wavelet analysis is approximately half at each filters, a consecutive application of wavelet transform can compress the measurement data, thus reducing the dimensionality of the signal, i.e., the antecedent. An SHDSL telecommunication line evaluation is used to demonstrate this type of applicability, wavelets help in this case to overcome the problem of a one dimensional signal sampling. In the case of using statistical functions, like mean, variance, gradient, edge density, Shannon or Rényi entropies for the extraction of the information from a picture or a measured data set, and they don not produce enough information for performing the classification well enough, one or two consecutive steps of wavelet analysis and applying the same functions for the thus resulting data can extend the number of antecedents, and can distill such parameters that were invisible for these functions in the original data set. We give two examples, two fuzzy classification schemes to show the improvement caused by wavelet analysis: a measured surface of a combustion engine cylinder and a colonoscopy picture. In the case of the first example the wear degree is to be determine, in the case of the second one, the roundish polyp content of the picture. In the first case the applied statistical functions are Rényi entropy differences, the structural entropies, in the second case mean, standard deviation, Canny filtered edge density, gradients and the entropies. In all the examples stabilized KH rule interpolation was used to treat sparse rulebases. The preliminary version of this paper was presented at the 3rd Conference on Information Technology, Systems Research and Computational Physics, 2–5 July 2018, Cracow, Poland [1].

Open Access: Yes

DOI: 10.1007/978-3-030-18058-4_5

Numerical study on the micro-mechanical behaviour of artificial granular materials

Majid Movahedi Rad M. Amine Benmebarek

Publication Name: Proceedings of the 2020 Session of the 13th Fib International Phd Symposium in Civil Engineering

Publication Date: 2020-01-01

Volume: Unknown

Issue: Unknown

Page Range: 86-93

Description:

Numerical models for the simulation of the micro-mechanical behaviour of granular assemblies have a wide range of applications, for instance in material science, process engineering, environmental engineering, railway engineering and geotechnical engineering (in this study we examined one macro-grain but what important is behaviour of granular assemblies). In this examination, experimental tests and numerical computations using the discrete element method (DEM) are carried out to evaluate the micro-mechanical behviour of the granular materials. For this purpose, artificial materials are taken into consideration for experimental Brazilian laboratory tests, and then according to the experimental results the DEM model is calibrated. Artificial crushable materials are produced by mixing cement and silt according to their mass ratio, in which cement can provide bonding and silt is the main filling material. In the DEM model, a 3D crushable granular material 'macro-grain' is built up from a large number of micro-grains which are associated according to crushable parallel bond properties. The behaviour of the single crushable grains and the fragmentation patterns under different contact configuration and load position are studied. The DEM simulation results show that the contact configuration type and load position affect the fragmentation patterns and loading capacity.

Open Access: Yes

DOI: DOI not available

Application of Integrated Development Approach in the Hungarian Urban Policy Process: The Road from Governance to Government

Somlyódyné Pfeil

Publication Name: Local and Urban Governance

Publication Date: 2020-01-01

Volume: Part F10

Issue: Unknown

Page Range: 65-90

Description:

The chapter investigates and discusses the impact of the political and administrative recentralisation process that has been going on in Hungary since 2011 on local government and urban governance, which has reduced the autonomy of both local and subnational self-governments. This chapter was written to confront the Hungarian urban policy with the challenges related to the new urban paradigm and the special principles of sustainable urban development defined in the New Urban Agenda, which was approved by the United Nations. The critical analysis identifies the tools of the state designed to penetrate more and more into the autonomy of local authorities and the impacts of these. Ist shines a light on the difficulties of the implementation of local governance by using the example of a post-socialist country. The chapter focuses on the role of large- and medium-sized Hungarian cities in the design and implementation of urban policy, based on the findings of an in-depth qualitative research made with city leaders. Throughout this, the analytical framework of the research is provided by multi-level governance and horizontal and vertical branches of cooperation and coordination. The findings point out that the operation of the Hungarian local governmental system has become fragmented in regard to urban and economic development. There are hardly any institutionalised arenas for horizontal cooperation, and unfortunately this is true for the cooperation among the governmental tiers. According to the conclusions drawn from the research, there is a tension between both the characteristics of the unitary nation state’s institutional structure and its urban policy and the elements of the New Urban Agenda. In the unitary state, the chances for the implementation of multi-level governance can be limited.

Open Access: Yes

DOI: 10.1007/978-3-030-47135-4_4