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Found 6278 publications

Advanced learning of fuzzy cognitive maps of waste management by bacterial algorithm

Miklós F. Hatwágner Claudiu Pozna Adrienn Buruzs László T. Kóczy

Publication Name: Proceedings of the 2013 Joint Ifsa World Congress and NAFIPS Annual Meeting Ifsa NAFIPS 2013

Publication Date: 2013-10-31

Volume: Unknown

Issue: Unknown

Page Range: 890-895

Description:

Fuzzy cognitive maps (FCMs) are a very convenient and simple tool for modeling complex systems. They are popular due to their simplicity and user friendliness. However, according to [1], human experts are subjective and can handle only relatively simple networks therefore there is an urgent need to develop methods for automated generation of FCM models. The present research deals with the methodology of FCMs in combination with the Bacterial Evolutionary Algorithm (BEA). The method of FCMs using BEA seems to be suitable to model such complex mechanisms as integrated municipal waste management (IMWM) systems. This paper is an attempt to assess the sustainability of the IMWM system by investigating the FCM methodology based on the BEA with a holistic approach. As a result, the best scenario to an IMWM system can be assigned. © 2013 IEEE.

Open Access: Yes

DOI: 10.1109/IFSA-NAFIPS.2013.6608518

Feeding models of wire antennas

Miklós Kuczmann

Publication Name: Przeglad Elektrotechniczny

Publication Date: 2011-04-26

Volume: 87

Issue: 3

Page Range: 107-110

Description:

Antenna parameters (e.g. input impedance, radiation pattern) can be measured in Full Anechoic Chambers (FAC). The simulated input impedance is depending on the applied feed model. The most frequently used models are the current probe model, the voltage gap generator, the magnetic frill generator and the waveguide port which are presented in this paper focusing on a simple example, a monopole antenna situated above a ground plane. The Finite Element Method (FEM) has been used in the numerical field analysis.

Open Access: Yes

DOI: DOI not available

Efficient Design and Sustainability Assessment of Wastewater Treatment Networks using the P-graph Approach: A Tannery Waste Case Study

Ákos Orosz Kirti M. Yenkie Jean Pimentel Emmanuel A. Aboagye Heriberto Cabezas Ferenc Friedler

Publication Name: Chemical Engineering Transactions

Publication Date: 2021-01-01

Volume: 88

Issue: Unknown

Page Range: 493-498

Description:

In the tannery industry approximately, 30 - 35 m3 of wastewater (WW) is generated per ton of rawhide processed. The WW comprises high concentrations of salts, ammonia, dye, solvents, and chromium. Of particular interest is chromium, which has been proven to cause dermatological, developmental, and reproductive issues on exposure. Thus, there is a need for appropriate treatment of the tannery WW before it is discharged for natural remediation. However, designing a treatment process is multifaceted due to the availability of multiple technologies that can perform similar tasks and the complex composition of waste streams. This necessitates the treatment to be performed in stages namely, primary, secondary, and tertiary. In some cases, pretreatment is required to enhance the recovery in the following stages. Due to the combinatorial nature of this problem, the P-graph approach, which uses principles from graph theory, can be used to synthesize a treatment pathway by selecting appropriate technologies at each stage, while meeting required purity specifications. Furthermore, the P-graph approach can provide alternate feasible treatment structures ranked based on Economics as well as Sustainability indicators, such as the Sustainable Process Index (SPI). In this work, a tannery WW case study is investigated with multiple stages and treatment technologies. A complex maximal structure is generated comprising all possible technologies, flows, connections, bypasses, mixers, and splitters. The models for each technology involve capital and operating costs, efficiency, and SPI at each stage of the treatment process. This problem is formulated in P-graph and solved using the Accelerated Branch-and-Bound algorithm.

Open Access: Yes

DOI: 10.3303/CET2188082

Identification and reconstruction of car body deformation applying tensor product models

István Harmati András Rövid Peter Varlaki Lászlõ Szeidl

Publication Name: Ines 2006 10th International Conference on Intelligent Engineering Systems 2006

Publication Date: 2006-12-01

Volume: Unknown

Issue: Unknown

Page Range: 98-101

Description:

Car body deformation modeling plays a very important role in crash accident analyses, as well as in safe car body design. The determination of the energy absorbed by the deformation and the corresponding Energy Equivalent Speed can be of key importance, however their precise determination is a very difficult task. Although, using the results of crash tests, intelligent and soft methods offer an automatic way to model the crash process itself, as well as to determine the absorbed energy, the before-crash speed of the car, etc. In this paper a modeling technique and an intelligent expert system are introduced which together are able to follow the deformation process of car bodies in car crashes and to analyze the strength of the different parts without any human intervention thus significantly can contribute to the improvement of the modeling, (automatic) design, and safety of car bodies. © 2006 IEEE.

Open Access: Yes

DOI: DOI not available

Integrated experimental design and nonlinear optimization to handle computationally expensive models under resource constraints

János D. Pintér Zoltán Horváth

Publication Name: Journal of Global Optimization

Publication Date: 2013-09-01

Volume: 57

Issue: 1

Page Range: 191-215

Description:

In many real-world applications of optimization, the underlying descriptive system model is defined by computationally expensive functions: simulation modules, numerical models and other "black box" model components are typical examples. In such cases, the model development and optimization team often has to rely on optimization carried out under severe resource constraints. To address this important issue, recently a Regularly Spaced Sampling (RSS) module has been added to the Lipschitz Global Optimizer (LGO) solver suite. RSS generates non-collapsing space filling designs, and produces corresponding solution estimates: this information is passed along to LGO for refinement within the given resource (function evaluation and/or runtime) limitations. Obviously, the quality of the solution obtained will essentially depend both on model instance difficulty and on the admissible computational effort. In spite of this general caveat, our results based on solving a selection of non-trivial global optimization test problems suggest that even a moderate amount of well-placed sampling effort enhanced by limited optimization can lead at least to reasonable or even to high quality results. Our numerical tests also indicate that LGO's overall efficiency is often increased by using RSS as a presolver, both in resource-constrained and in completed LGO runs. © 2012 Springer Science+Business Media, LLC.

Open Access: Yes

DOI: 10.1007/s10898-012-9882-7

Maize yield prediction based on artificial intelligence using spatio-temporal data

G. Milics Bálint Daróczy C. Kerepesi A. J. Kovács A. Nyéki M. Neményi András Benczúr

Publication Name: Precision Agriculture 2019 Papers Presented at the 12th European Conference on Precision Agriculture Ecpa 2019

Publication Date: 2019-01-01

Volume: Unknown

Issue: Unknown

Page Range: 1011-1017

Description:

The aim of this study was to predict maize yield by artificial intelligence using spatio-temporal training data. Counter-propagation artificial neural networks (CP-ANNs), XY-fused networks (XY-Fs), supervised Kohonen networks (SKNs), extreme gradient boosting (XGBoost) and support-vector machine (SVM) were used for predicting maize yield in 5 vegetation periods. Input variables for modelling were: soil parameters (pH, P2O5, K2O, Zn, Clay content, ECa, draught force, Cone index), and micro-relief averages and meteorological parameters for the 63 treatment units. The best performing method (XGBoost) attained 92.1 and 95.3% of accuracy on the training and the test set.

Open Access: Yes

DOI: 10.3920/978-90-8686-888-9_124

Characterization of fatty acid, antioxidant, and polyphenol content of grape seed oil from different Vitis vinifera L. varieties

E. Lakatos V. Kapcsándi Székelyhidi Rita Beatrix Sik László Ádám Linka

Publication Name: OCL Oilseeds and Fats Crops and Lipids

Publication Date: 2021-01-01

Volume: 28

Issue: Unknown

Page Range: Unknown

Description:

In this study, we examined the yield and oil quality of eight different grape varieties. For the experiments, the grape seeds were obtained from the Benedictine Pannonhalma Archabbey in the northwestern region of Hungary. The aim of the studies was to determine the oil yield obtained by extraction and to examine the differences between the fatty acid composition, antioxidant capacity, and total polyphenol content of the oils of different grape varieties. Based on the results, the oil content of the grape seeds varied between 99.91 g/kg and 126.74 g/kg. The grape seed oils analysed contained significant amounts of stearic acid (3.42-9.93%), palmitic acid (7.81-10.66%), oleic acid (14.29-19.92%), and linoleic acid (66.85-72.47%). Besides, the grape seed oils tested contained several other fatty acids in small amounts. There were significant differences in the total antioxidant and total polyphenol content of the oils. Total polyphenol content ranged from 0.24 to 1.13 mg GAE/g, while the total antioxidant content changed between 0.12 and 0.78 μg TEAC/g. The results show that the studied varieties are suitable for the production of table grape seed oil based on their oil yield, and the oils have favourable, health-protecting properties in terms of their quality.

Open Access: Yes

DOI: 10.1051/ocl/2021017

Can It Still Be Used? Compression Strength Recovery of Corrugated Boxes After Moisture Exposure

Péter Böröcz Péter Csavajda

Publication Name: Chemical Engineering Transactions

Publication Date: 2025-01-01

Volume: 121

Issue: Unknown

Page Range: 43-48

Description:

Moisture exposure is a common risk for corrugated fiberboard boxes (CFB) during transport, handling, or storage, especially in humid environments or due to accidental water contact. Boxes that have gotten wet are often seen as unsafe and not strong, so they are thrown away. However, this practice contributes to unnecessary material waste and higher environmental impact. This study aims to examine whether corrugated boxes that have been exposed to water and subsequently dried can retain sufficient compression strength to allow for safe use. In this study, the potential for strength recovery of CFB following water exposure and drying was investigated. The samples were immersed in water for a defined period to simulate realistic exposure scenarios, then dried under controlled conditions. Following this, Box Compression Tests (BCT) were carried out to evaluate the remaining compression strength. The results showed that while compression strength decreases due to water exposure, a significant portion of it can be recovered after drying, depending on the material structure and exposure duration, with reductions ranging from 17 % to 31 %. These findings suggest that moisture-affected boxes may remain suitable for use, which questions the default approach of immediate disposal. By quantifying post-drying strength loss, this research supports data-driven decisions in packaging use, potentially reducing material waste and promoting more sustainable logistics practices.

Open Access: Yes

DOI: 10.3303/CET25121008

Warping transfer superelement model for bolted end-plate connections subject to 3D loads

B. Vaszilievits-Sömjén Majid Movahedi Rad J. Szalai

Publication Name: Stability and Ductility of Steel Structures Proceedings of the International Colloquia on Stability and Ductility of Steel Structures 2019

Publication Date: 2019-01-01

Volume: Unknown

Issue: Unknown

Page Range: 1210-1217

Description:

A simple beam element based modelling technique has been developed which makes possible to analyze frames made of I sections with column-rafter bolted end-plate connections, subject to 3D loads, compatible with the thin walled beam theory with 7DOF beam elements. The model previously developed by the same team for welded connections has been ex-tended with the addition of linear spring elements to model the bolts located at the upper and lower beam flange level. The spring stiffnesses are calculated based on the extension of the Eurocode component method and verified by simulations performed with FEA software Abaqus.

Open Access: Yes

DOI: DOI not available