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Found 6414 publications

Interpolation in homogenous fuzzy signature rule bases

Laszlo T. Koczy

Publication Name: IEEE International Conference on Fuzzy Systems

Publication Date: 2017-08-23

Volume: 0

Issue: Unknown

Page Range: Unknown

Description:

Fuzzy signature sets (FSigSets) are extensions of the original fuzzy set concept, and also of the Vector Valued Fuzzy Set notion. In a FSigSet rule base the (input) universe of discourse X is mapped into a set of hierarchically grouped fuzzy sets, and each element of X has a 'membership degree' consisting of a rooted tree with membership degrees at each leaf and aggregations at the intermediate vertices. The structure of the tree is identical for each element in the case of homogenous FSigSets, and so are the aggregations, depending only on the position of the vertex. Interpolation in fuzzy rule bases allows the calculation of a conclusion in the output universe Y belonging to an observation even if there are gaps in the rule base and the observation does not intersect with any of the antecedent sets. The key question here is how to determine the degree of similarity, or inversely, the distance, of any observation from the surrounding antecedents of the rules in the base, so that the distance incorporates the information involved with the close connection of the features in the sub-groups, and the aggregations expressing the form of this connection. A solution is proposed, and a pair of numerical examples is presented.

Open Access: Yes

DOI: 10.1109/FUZZ-IEEE.2017.8015393

Vaporization Dynamics of a Dissipative Quantum Liquid

Ádám Bácsi Balázs Dóra Balázs Dóra Cǎtǎlin Paşcu Moca Gergely Zarand

Publication Name: Physical Review Letters

Publication Date: 2020-12-30

Volume: 125

Issue: 26

Page Range: Unknown

Description:

We investigate the stability of a Luttinger liquid, upon suddenly coupling it to a dissipative environment. Within the Lindblad equation, the environment couples to local currents and heats the quantum liquid up to infinite temperatures. The single particle density matrix reveals the fractionalization of fermionic excitations in the spatial correlations by retaining the initial noninteger power law exponents, accompanied by an exponential decay in time with an interaction dependent rate. The spectrum of the time evolved density matrix is gapped, which collapses gradually as -ln(t). The von Neumann entropy crosses over from the early time -tln(t) behavior to ln(t) growth for late times. The early time dynamics is captured numerically by performing simulations on spinless interacting fermions, using several numerically exact methods. Our results could be tested experimentally in bosonic Luttinger liquids.

Open Access: Yes

DOI: 10.1103/PhysRevLett.125.266803

Energy absorption modelling technique for car body deformation

Istvan A. Harmati András Rövid Peter Varlaki

Publication Name: Saci 2007 4th International Symposium on Applied Computational Intelligence and Informatics Proceedings

Publication Date: 2007-10-01

Volume: Unknown

Issue: Unknown

Page Range: 269-272

Description:

The main object of this paper is to introduce a model for describing how the enrgy distribution changes during deformational processes, esp. in car crashes. This an important and difficult task in accident analysis and in safety car-body design. Exact estimation or measuring of the absorbed energy by the deformation is almost impossible. The classical tool for this task is usually a differental equation based finite element method, which requires exact knowledge about the parameters and takes a lot of computational time with high complexity. In the following we introduce a simple numerical model for the changing of the energy distribution during the whole deformational process. © 2007 IEEE.

Open Access: Yes

DOI: 10.1109/SACI.2007.375523

Measurement and Analysis of Vibration Levels in Rail Transport in Central Europe

Péter Böröcz S. Paul Singh

Publication Name: Packaging Technology and Science

Publication Date: 2017-08-01

Volume: 30

Issue: 8

Page Range: 361-371

Description:

In the last decade, with a continued change in world economic conditions and global trade, transportation of goods has continued to increase. The opening of new and existing markets requires that products and packages move through various regions of the world using available logistical equipment and networks at a faster pace. It also requires that damage be kept at a minimum while providing maximum safety to individuals. This can be achieved by properly designing packages to transportation levels that occur in the supply chain. The purpose of this research is to both measure and analyse the vibration physical forces that occur during rail transport. Rail shipments are widely used across the world, and they are an integral part of the intermodal transfer of ISO containers from ships and trucks to rail. The aim of this paper is to provide vibration levels measured for rail shipments on a major railway line in Central Europe that has not been previously published. The vibration levels that were measured in this study were compared with American Society of Testing and Materials, United States Military Standards and United Kingdom Defense Standard standards and International Safe Transit Association procedures in the form of power spectral density spectrums. A composite power spectral density spectrum is provided which can be used to simulate the measured rail vibration levels in Central Europe. Results are also compared with rail travel in other international shipments for North America and Asia. Copyright © 2016 John Wiley & Sons, Ltd.

Open Access: Yes

DOI: 10.1002/pts.2225

An effective Discrete Bacterial Memetic Evolutionary Algorithm for the Traveling Salesman Problem

Péter Földesi Boldizsár Tüu-Szabó Laszlo T. Koczy

Publication Name: International Journal of Intelligent Systems

Publication Date: 2017-08-01

Volume: 32

Issue: 8

Page Range: 862-876

Description:

In recent years, a large number of evolutionary and other population-based heuristics were proposed in the literature. In 2009, we suggested to combine the very efficient bacterial evolutionary algorithm with local search as a new Discrete Bacterial Memetic Evolutionary Algorithm (DBMEA) (Farkas et al., In: Towards intelligent engineering & information technology, Studies in Computational Intelligence, Vol 243. Berlin, Germany: Springer-Verlag; 2009. pp 607–625). The method was tested on one of Traveling Salesman Problem (TSP) benchmark problems, and a difference was found between the real optimum calculated by the new and the published result because the Concorde and the Lin–Kernighan algorithm use an approximation substituting distances of points by the closest integer values. We modified the Concorde algorithm using real cost values to compare with our results. In this paper, we systematically investigate TSPLIB benchmark problems and other VLSI benchmark problems (http://www.math.uwaterloo.ca/tsp/vlsi/index.html) and compare the following values: optima found by the DBMEA heuristic and by the modified Concorde algorithm with real cost values, run times of DBMEA, modified Concorde, and Lin–Kernighan heuristic. In this paper, for the evaluation of metaheuristic techniques, we suggest the usage of predictability of the successful run in addition to the accuracy of the result and the computational cost as third property. We will show that in the case of DBMEA, the run time is more predictable than in the case of Concorde algorithm, so we suggest the use of DBMEA heuristic as very efficient for the solution of TSP and other nondeterministic polynomial-time hard optimization problems.

Open Access: Yes

DOI: 10.1002/int.21893

Product Related Values and Sustainability – Deeper Understanding of the Millennials

Adrienn Dernóczy-Polyák Kornelia Osieczko-Potoczna Attila Kurucz

Publication Name: Chemical Engineering Transactions

Publication Date: 2023-01-01

Volume: 107

Issue: Unknown

Page Range: 151-156

Description:

In addition to increasing productivity, digitisation and automation are an important part of the sustainability issue. Therefore, investments aimed at environmental protection and long-term sustainability appear to be on the rise among companies with strong innovation activities in the industrial environment. This article presents the results of a study that outlines young people's assessment of the automation and digitisation opportunities on offer. In addition to traditional values, the goal is to find out how they perceive the importance of Industry 4.0 solutions in shaping the way a company operates. The survey was conducted in two countries, Hungary and Poland. It sought to answer the question of how groups, which by definition are well-defined by certain demographic characteristics, determine their preferences with regard to the above-mentioned areas and how they differentiate them. Relationships between clusters - based on preference-related differences - with respect to product manufacturing, i.e., variables that are considered important to companies, were examined. It can be concluded that the environmental issues and, due to this, sustainability is not equally important (range: 3.512 to 4.308). The traditional features of the products were important for everyone (4,407 to 4,549), and the smart features were differently evaluated (2,607 to 3,386). Overall, looking at the relationship between sustainability-related values will bring us closer to further typology and a better understanding of the clusters, making them more accessible and easier to understand and thus enabling a more effective strategy to be implemented with a focus on sustainability.

Open Access: Yes

DOI: 10.3303/CET23107026

The firm geography of Central and Eastern Europe and the Western Balkans

Szilárd Rácz Ildikó Egyed Ádám Páthy Judit Berkes

Publication Name: Journal of Urban and Regional Analysis

Publication Date: 2025-01-01

Volume: 17

Issue: 1

Page Range: 5-35

Description:

Over the past three decades, significant socio-economic transformations have reshaped the post-socialist states of Central and Eastern Europe. This study examines the geography of firms with over 10 employees across 15 countries: Albania, Austria, Bosnia and Herzegovina, Bulgaria, Croatia, Czechia, Hungary, Kosovo, Montenegro, North Macedonia, Poland, Romania, Serbia, Slova-kia, and Slovenia. Using data from over 300,000 firms, the analysis focused on firm size categories, turnover, and activity distribution. The research highlighted disparities between post-socialist and other countries, and it employed descriptive statistics and the framework of agglomeration economies to uncover nuanced spatial patterns. The findings revealed significant differences in business concentration and the functions of small and medium-sized cities, particularly in the regions without a European-scale metropolis, emphasising their role in regional economic and demographic sustainability.

Open Access: Yes

DOI: 10.37043/JURA.2025.17.1.1

The impact of marketing strategy on logistics decisions and the implementation of JIT

Péter Földesi Eszter Sós

Publication Name: Acta Technica Jaurinensis

Publication Date: 2021-11-24

Volume: 14

Issue: 4

Page Range: 364-376

Description:

Marketing has a significant impact on logistics systems and corporate performance, so it is nowadays necessary to define a marketing logistics strategy in the lives of larger companies so that logistics decisions are not distorted by the marketing strategy. According to the current direction of development, smaller and smaller quantities of goods are constantly being moved, with ever shorter deadlines. Therefore, companies prefer to use the Just In Time (JIT) system, which results in a gradual reduction in inventory costs, but increases the burden on the environment. In this article, we analyze the interaction between marketing and logistics and the logistics environment required to implement a JIT system. For research we have used the matrix of Quality Function Deployment (QFD) technique to evaluate the needs of the customer with respect to the JIT system, thus clarifying the logistics strategy applicable to the introduction of the specific product.

Open Access: Yes

DOI: 10.14513/actatechjaur.00597

Treno Di Notte Greta Thunberg: the Meaning of Sustainability in the Overnight Rail Passenger Market – A Case Study on the Route Hungary – Italy

Zsolt Lévai Balázs Molnár

Publication Name: Chemical Engineering Transactions

Publication Date: 2023-01-01

Volume: 107

Issue: Unknown

Page Range: 367-372

Description:

This study deals with sustainability issues in transport, focusing on rail and air transport. The background to the research is the need to reduce the carbon footprint of transport, which includes prioritising rail. The current developments in the world: the rise of climate protection and sustainability, increasingly environmentally conscious lifestyles, and the growing media attention on these issues (including Greta Thunberg's activity) suggest that long-distance environmental friendly vehicles like overnight rail passenger trains is likely more to use in Europe. This makes it necessary to improve the rail services. However, previous studies have dealt separately with the environmental issues and the railway development. That is why the scope of the research is to link these two separate topics. In order to achieve the future objectives of the (night) rail market, it is necessary to define what can be meant by rail sustainability, so that the environmental friendliness of this transport mode can be clearly expressed to the public. Therefore, the aim of this research is to determine the relationship between the less polluting rail sub-sector and sustainability by analysing night rail travel compared to short-haul air travel. As a result, the definition of sustainability in rail transport and a case study with the practice of product design methodologies that increase the role of the railway are presented. With the rise of the (night) rail transport, fewer flights will be needed.

Open Access: Yes

DOI: 10.3303/CET23107062