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Publications - 6289

New alternatives to private car transport for different powertrains in Hungary - Trends in the petrol, diesel and electric drive solutions

Eniko Nagy Karl Eva Mark Viktor Katai Gyorgy Molnar

Publication Name: Ines 2025 29th IEEE International Conference on Intelligent Engineering Systems 2025 Proceedings

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: 285-289

Description:

As time passes and technology becomes more impressive, more ways exist to process, store and visualise data, contributing to data analytics' power. The most common process is to collect data from different sources and store it in some file format. Some process then passes the acquired information to a data warehouse where the data can be stored and queried. Once the right data and tables have been selected, they are imported and exported to a visualisation system, where reports can be generated from the available information. All that remains is to create a custom website where the reports can be displayed. In this paper, we work with data related to petrol, diesel, and electric vehicles. The dataset was synthetically generated using a simulation model developed by the author to reflect realistic automotive scenarios. An ETL process will import the data into the data warehouse, which will be stored for subsequent analysis. The information is then exported from the data warehouse to be processed by the visualisation program and used to make statements. This process aims to demonstrate how the values derived from the generated data transition from their raw form to a visualised state. Given the current global transformation of the automotive industry, this topic was selected due to its relevance and the widespread impact of these changes. The study aims to generate various analytical statements, such as the average engine power across different car brands or the average fuel consumption per 100 kilometres for specific vehicle types.

Open Access: Yes

DOI: 10.1109/INES67149.2025.11078211

Two Stages Outlier Removal as Pre-Processing Digitizer Data on Fine Motor Skills (FMS) Classification Using Covariance Estimator and Isolation Forest

Surya Sumpeno A. Tormási Nurul Zainal Fanani Festa Yumpi Rahmanawati K. Khamid Adri Gabriel Sooai Mauridhi Hery Purnomo László T. Kóczy

Publication Name: International Journal of Intelligent Engineering and Systems

Publication Date: 2021-08-01

Volume: 14

Issue: 4

Page Range: 571-582

Description:

The increase of the classification accuracy level has become an important problem in machine learning especially in diverse data-set that contain the outlier data. In the data stream or the data from sensor readings that produce large data, it allows a lot of noise to occur. It makes the performance of the machine learning model is disrupted or even decreased. Therefore, clean data from noise is needed to obtain good accuracy and to improve the performance of the machine learning model. This research proposes a two-stages for detecting and removing outlier data by using the covariance estimator and isolation forest methods as pre-processing in the classification process to determine fine motor skill (FMS). The dataset was generated from the process of recording data directly during cursive writing by using a digitizer. The data included the relative position of the stylus on the digitizer board. x position, y position, z position, and pressure values are then used as features in the classification process. In the process of observation and recording, the generated data was very huge so some of them produce the outlier data. From the experimental results that have been implemented, the level of accuracy in the FMS classification process increases between 0.5-1% by using the Random Forest classifier after the detection and outlier removal by using covariance estimator and isolation forest. The highest accuracy rate achieves 98.05% compared to the accuracy without outlier removal, which is only about 97.3%.

Open Access: Yes

DOI: 10.22266/ijies2021.0831.50

Topological and energetic conditions for lithographic production of carbon nanotubes from graphene

Ibolya Zsoldos Istvan Laszlo David Fulep

Publication Name: Journal of Nanomaterials

Publication Date: 2015-01-01

Volume: 2015

Issue: Unknown

Page Range: Unknown

Description:

Density Functional Based Tight-Binding (DFTB) molecular dynamics (MD) simulations were performed for producing carbon nanotubes from graphene nanoribbons. The constant temperature simulations were controlled with the help of Nosé-Hoover thermostat. In our systematic study we obtained critical curvature energies and determined topological conditions for nanotube production from two parallel graphene nanoribbons. We obtained linear relationship between the curvature energy and the square of the curvature.

Open Access: Yes

DOI: 10.1155/2015/379563

Maximal entropy and minimal variability OWA operator weights: A short survey of recent developments

Christer Carlsson Robert Fuller

Publication Name: Studies in Fuzziness and Soft Computing

Publication Date: 2018-01-01

Volume: 357

Issue: Unknown

Page Range: 187-199

Description:

The determination of ordered weighted averaging (OWA) operator weights is a very important issue of applying the OWA operator for decision making. One of the first approaches, suggested by O’Hagan, determines a special class of OWA operators having maximal entropy of the OWA weights for a given level of orness; algorithmically it is based on the solution of a constrained optimization problem. In 2001, using the method of Lagrange multipliers, Fullér and Majlender solved this constrained optimization problem analytically and determined the optimal weighting vector. In 2003 Fullér and Majlender computed the exact minimal variability weighting vector for any level of orness using the Karush-Kuhn-Tucker second-order sufficiency conditions for optimality. The problem of maximizing an OWA aggregation of a group of variables that are interrelated and constrained by a collection of linear inequalities was first considered by Yager in 1996, where he showed how this problem can be modeled as a mixed integer linear programming problem. In 2003 Carlsson, Fullér and Majlender derived an algorithm for solving the constrained OWA aggregation problem under a simple linear constraint: the sum of the variables is less than or equal to one. In this paper we give a short survey of numerous later works which extend and develop these models.

Open Access: Yes

DOI: 10.1007/978-3-319-60207-3_12

Practical stability design of general I-section members for combined forces

B. Vaszilievits-Sömjén Donald W. White

Publication Name: Proceedings of the Annual Stability Conference Structural Stability Research Council Ssrc 2025

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Numerous situations occur in engineering practice where I-section members must be designed for a combination of flexure, shear, torsion, and/or axial loadings. Particularly in metal buildings and horizontally curved I-girder bridges, these member types may have variable web depth and stepped cross-section transitions along their length. Design guidance for handling combined loadings on these member types has been limited. Modern software systems that can accurately calculate combined second-order elastic demands and elastic buckling loads for general I-section members in general framing systems are increasingly available. This paper discusses new AISC 360 Chapter F provisions under consideration in the 2027 Specification development cycle. These provisions provide an improved, streamlined calculation of the flexural resistance of general I-section members. The calculations address recent research findings regarding the influence of moment gradient and corresponding web shear. The discussion of the new AISC 360 procedures is followed by a brief presentation of recommended ways to verify a design where the member is also subjected to axial compression and/or torsion based on experiences from European and American practice. The focus of the paper is on the essential concepts.

Open Access: Yes

DOI: DOI not available

Dem modeling of crushable grain material under different loading conditions

Majid Movahedi Rad M. Amine Benmebarek

Publication Name: Periodica Polytechnica Civil Engineering

Publication Date: 2021-07-13

Volume: 65

Issue: 3

Page Range: 935-945

Description:

This paper deals with the effect of contact conditions on the crushing mechanisms and the strength of granular materials. The computation of crushable grain material under different loading conditions is performed using 3D model of discrete element method (DEM). The crushable macro-grain is generated from a large number of identical spherical micro-grains which are connected according to the bonded particle model. First, the parameters of the proposed DEM model are calibrated to match the force-displacement curve obtained from Brazilian Tests performed on cylinders made of artificially crushable material. The damage profile right at the point when the force-displacement curve reaches its maximum is seen to replicate the same crack patterns observed in Brazilian test experiments. Then, parametric investigations are performed by varying the coordination number, the contact location distribution, and the contact area. The results show that these parameters play a significant role in determining the critical contact force and fracture mechanism of crushable particles compared to a traditional macro-grain crushing test. Increasing distribution and coordination number of the macro-grain increases particle strength when large area contact is permitted. However, for linear contact area, the effect of increasing coordination number on particle strength is marginal.

Open Access: Yes

DOI: 10.3311/PPci.17948

Assessing uncertainty of driver's distinguishing between built-up and nonbuilt up areas

Gabriella Kosztolanyi-Ivan

Publication Name: Pollack Periodica

Publication Date: 2013-08-01

Volume: 8

Issue: 2

Page Range: 87-96

Description:

The safe speeds and also the general speed limits are quite different outside and within built-up areas. If it does not follow from the road design, whether the given scene is within or outside built-up area, drivers are uncertain about their appropriate speed.This paper shows two approaches to assess the degree of uncertainty of the drivers. The first was a questionnaire survey of requested speeds at various road scenes. In the second method, the recognition process of drivers was simulated by image classification software.Output indicators of these methods (standard deviation of speeds and certainty score) can serve as tools to identify road scenes and road elements leading to uncertain and therefore risky situations.

Open Access: Yes

DOI: 10.1556/Pollack.8.2013.2.10

Mathematics and computational intelligence synergies for emerging challenges

Eloísa Ramírez-Poussa Juan Moreno-García László T. Kóczy Jesús Medina-Moreno

Publication Name: International Journal of Computational Intelligence Systems

Publication Date: 2021-01-01

Volume: 14

Issue: 1

Page Range: 818-820

Description:

No description provided

Open Access: Yes

DOI: 10.2991/ijcis.d.210121.001

Beliefs about plant-based diet based in a sample of Hungarian females

Péter Huszka Veronika Keller

Publication Name: Ukrainian Food Journal

Publication Date: 2023-01-01

Volume: 12

Issue: 3

Page Range: 398-418

Description:

Introduction. The aim of research is to examine the knowledge about plant-based diets, what beliefs and misconceptions exist about plant-based diets (PBDs), and how these differ between lifestyle groups among Hungarian females. Materials and methods. Data were collected through an online survey on social media. These data were processed using univariate statistics (general description of the sample), exploratory factor analysis (identification of healthy lifestyles), cluster analysis (segmentation purposes), chi-square statistics (cluster profiling), F-statistics (comparing attitudes toward PBDs), and cross tabulation (knowledge and perceptions of PBDs). Results and discussion. Four health-related lifestyle dimensions (health-conscious eating, mindfulness, carbohydrate avoidance, red meat avoidance) were identified, and four segments emerged (healthy food choosers, red meat avoiders, stress-free women, rejecters). Healthy food choosers (40.9%) prioritize healthy eating, avoid sugary snacks, and monitor carbohydrate intake. Red meat avoiders (27.9%) are neutral about healthy eating, but avoid red meat and processed foods; don't focus on carbohydrates. Stress-free women (20.8%) value mindfulness, relaxation, and outdoor physical activity for a stress-free life. Rejecters (10.4%) have a negative attitude toward healthy eating, mindfulness, carbohydrates, and red meat. Red meat avoiders live in the capital city, eat fruits and vegetables more often or at least once a day. Rejecters live in villages and eat fruits and vegetables every 4–5 days in a week or do not eat fruits and vegetables in a week. Healthy eaters eat fruits and vegetables more times a day. Stress-free people eat fruits and vegetables every 2–3 days in a week. They differed in their knowledge, attitudes and perceptions of PBDs. 72.1% of healthy food choosers, 84.8% of red meat avoiders, 75.8% of stress-free people and 71.9% of rejecters thought that plant-based diet was similar to vegan and vegetarian diet. The attitudes range from “may have health benefits for certain diseases” as the attitude with the highest mean level of agreement (4.26), especially among red meat avoiders, to “encourages diary consumption” as the attitude with the lowest mean level of agreement (1.69), especially among red meat avoiders. Red meat avoiders, healthy food choosers, and stress-free women had more positive attitudes toward PBDs than did rejecters. The majority of females were thinking about trying out PBDs. Red meat avoiders, healthy eaters, and stress-free women had more positive attitudes toward PBD than did rejecters. Healthy eaters perceived PBD as healthy. Red meat avoiders perceived the plant-based diet as healthy, safe, varied, exciting, environmentally friendly, and a complete diet. Stress-free women thought the plant-based diet was unhealthy and environmentally unfriendly. Rejecters attached more negative attributes to the PBD. They perceived the meatless diet as unhealthy, dangerous, monotonous, boring, environmentally unfriendly, difficult to digest, and malnutrition. Conclusions The results contribute to the literature by adding empirical evidence to the emerging trends (PBD, vegan, vegetarian diets), as well as generating suggestions for nutrition and dietetics professionals and the government, as targeted marketing programs can be planned to change dietary behavior.

Open Access: Yes

DOI: 10.24263/2304-974X-2023-12-3-7