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Found 6674 publications

Modeling of distribution of visible and non-visible graphite nodules embedded in the surface layer of ductile cast iron

Ágnes Csizmazia Imre Czinege Mihaly Réger Tamás Réti

Publication Name: Materials Science Forum

Publication Date: 2010-01-01

Volume: 659

Issue: Unknown

Page Range: 453-458

Description:

The graphite nodule count and size distribution are important structural parameters in the quantitative characterization of the microstructure of ductile cast irons. In several cases, it is observed that local surface damages (cracks or microchip formations) are generated by the final manufacturing process (superfinishing operation), and these defects are originated basically from the hidden (invisible) graphite nodules located directly below surface. Based on measured data obtained by an image analyzer, a stereological model and a simulation algorithm have been developed to analyse the correspondances between the graphite morphology and the defect formation. This method makes it possible to establish a correlation between the microstructure parameters and the occurrence of local surface defects on ductile cast iron components. © (2010) Trans Tech Publications.

Open Access: Yes

DOI: 10.4028/www.scientific.net/MSF.659.453

Methods to detect and measure scour around bridge foundations

Muhanad Al-Jubouri Richard P. Ray

Publication Name: Acta Technica Jaurinensis

Publication Date: 2021-11-24

Volume: 14

Issue: 4

Page Range: 631-649

Description:

Bridges are indispensable structures vital to the operation of road and rail transportation networks. Crossing rivers and artificial waterways, however, presents a risk to their foundations due to scour actions. Scour is the number one cause for bridge failures and may occur beneath any bridge, large or small, with supports located within the waterway. This paper provides a summary of present scour detection and measurement equipment and associated assessment methodologies. In this regard, particular emphasis is placed on structural health monitoring better to evaluate the presence and influence of potential scour. A Sensitivity Analysis on a newly introduced monitoring system is also assumed. Furthermore, much research has been undertaken to create a technology that can instantly identify and detect bridge scour, improving survey reliability through prior inspection and prompt intervention. This research will explore and evaluate bridge scour detection methods employed and suggest a possible path for developing the detection system to identify scour depth effectively and efficiently. Finally, our key aim is to minimize human effort in identifying and bridge scour by using a quick, easy-to-use, cost-effective process, resulting in fewer injuries and economic savings.

Open Access: Yes

DOI: 10.14513/actatechjaur.00626

Criticality analysis of purchased materials based on fuzzy signatures

Péter Földesi Gábor Farkas László T. Kóczy

Publication Name: IEEE International Conference on Fuzzy Systems

Publication Date: 2017-08-23

Volume: 0

Issue: Unknown

Page Range: Unknown

Description:

Selecting and evaluating the suppliers represent a very complex task, because a wide range of attributions must be taken into consideration and many of them are difficult to be made objectively quantified. The aim of this research is to provide a new model based on fuzzy signatures for selecting and evaluating the critical parts for the production.

Open Access: Yes

DOI: 10.1109/FUZZ-IEEE.2017.8015649

Detraining Slows and Maintenance Training Over 6 Years Halts Parkinsonian Symptoms-Progression

Tibor Hortobágyi József Tollár Dávid Sipos Gergely Sántha Ward Nieboer Gábor Borbély György Áfra Emese Reichardt-Varga Katalin Tamási

Publication Name: Frontiers in Neurology

Publication Date: 2021-11-19

Volume: 12

Issue: Unknown

Page Range: Unknown

Description:

Introduction: There are scant data to demonstrate that the long-term non-pharmaceutical interventions can slow the progression of motor and non-motor symptoms and lower drug dose in Parkinson's disease (PD). Methods: After randomization, the Exercise-only (E, n = 19) group completed an initial 3-week-long, 15-session supervised, high-intensity sensorimotor agility exercise program designed to improve the postural stability. The Exercise + Maintenance (E + M, n = 22) group completed the 3-week program and continued the same program three times per week for 6 years. The no exercise and no maintenance control (C, n = 26) group continued habitual living. In each patient, 11 outcomes were measured before and after the 3-week initial exercise program and then, at 3, 6, 12, 18, 24, 36, 48, 60, and 72 months. Results: The longitudinal linear mixed effects modeling of each variable was fitted with maximum likelihood estimation and adjusted for baseline and covariates. The exercise program strongly improved the primary outcome, Motor Experiences of Daily Living, by ~7 points and all secondary outcomes [body mass index (BMI), disease and no disease-specific quality of life, depression, mobility, and standing balance]. In E group, the detraining effects lasted up to 12 months. E+M group further improved the initial exercise-induced gains up to 3 months and the gains were sustained until year 6. In C group, the symptoms worsened steadily. By year 6, levodopa (L-dopa) equivalents increased in all the groups but least in E + M group. Conclusion: A short-term, high-intensity sensorimotor agility exercise program improved the PD symptoms up to a year during detraining but the subsequent 6-year maintenance program was needed to further increase or sustain the initial improvements in the symptoms, quality of life, and drug dose.

Open Access: Yes

DOI: 10.3389/fneur.2021.737726

The Role of Economic Growth and FDI in Ecological Footprint and the Load Capacity Factor: Evidence From Türkiye

Zafer Adali Ayyüce Memiş Karataş Xin Zhao İlkay Güler Gökçen Aydinbaş

Publication Name: Acta Montanistica Slovaca

Publication Date: 2025-01-01

Volume: 30

Issue: 1

Page Range: 193-208

Description:

Proposed sustainable economic development and growth have been among the leading and desired objectives of policymakers. Thus, various investigations have been conducted, considering different social, political, and economic factors to lessen environmental degradation and improve biocapacity. Within this context, Türkiye is one of the most essential cases because of its location and role in the global supply chain, emerging countries' members, and the severity of the environmental situation. Thus, the study employs the Fourier ARDL, FADL co-integration tests, FMOLS estimations with Fourier Terms, and Fourier Toda-Yamamoto analysis to investigate the role of economic growth and FDI in ecological footprint and the load capacity factor along with considering some control variables over the period between 1982 to 2021. As a result of the investigations, it is concluded that the economic growth, the FDI, and the remaining variables do not promote impact the load capacity factor. However, the considered variables pressure the environment when the ecological footprint is regarded as the environmental indicator, and the pollution haven hypothesis holds for Türkiye. To reverse and mitigate the harmful effects of economic activities, efforts, and policies should be made toward environmentally friendly forms of production, trade, FDI, and renewable energy sources.

Open Access: Yes

DOI: 10.46544/AMS.v30i1.15

On the existence and uniqueness of fixed points of fuzzy set valued sigmoid fuzzy cognitive maps

István Harmati László T. Kóczy

Publication Name: IEEE International Conference on Fuzzy Systems

Publication Date: 2018-10-12

Volume: 2018-July

Issue: Unknown

Page Range: Unknown

Description:

Fuzzy cognitive maps are decision support tools, where the complex structure is modelled by a weighted, directed graph. The nodes represent specific characteristics of the modelled system, weighted and directed edges correspond to the direction and the strength of the relationship between the factors. The system state is identified by the values of the nodes which are computed by iteration. This process may lead to a fixed point, a limit cycle or produces chaotic behaviour. The type of behaviour depends on the weights, on the topology of the graph and on the function applied for the iteration. From the practical viewpoint, it is critical to know whether the iteration converges to a fixed point or not. In this article, we discuss this problem for the case when the weights or the values of the nodes are fuzzy numbers. This scenario may occur when linguistic variables, modelled by fuzzy numbers, describe the connections.

Open Access: Yes

DOI: 10.1109/FUZZ-IEEE.2018.8491447

Antioxidant and polyphenol content of different Vitis vinifera seed cultivars and two facilities of production of a functional bakery product

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

Publication Name: Chemical Papers

Publication Date: 2021-11-01

Volume: 75

Issue: 11

Page Range: 5711-5717

Description:

This study aimed to examine the differences between the antioxidant capacity, and the total polyphenol content of the seed of eight different grape varieties. We also attempt to create a functional loaf enriched with grape seed meal. To achieve this goal, 3, 6, and 9% of the grape seed meal were added to the loaves made of bread flour and gluten-free flour mixture, and then the changes in their antioxidant and polyphenol content were examined. Based on the results, there were significant differences between the polyphenol and antioxidant content of grape seed varieties. The antioxidant content of the grape seeds varied between 228.50 mg AAE/g (94.80 mg TE/g) and 438.33 mg AAE/g (181.86 mg TE/g) in case of fatty samples, and between 176.29 mg AAE/g (41.24 mg TE/g) and 424.91 mg AAE/g (99.40 mg TE/g) in case of defatted samples. The total polyphenol content of the fatty samples changed between 91.16 and 221.81 mg GAE/g; in case of defatted samples, it ranged from 46.01 to 207.68 mg GAE/g. Rhine Riesling contained the greatest amount of these compounds. The functionality of loafs was confirmed by spectrophotometric analysis. Total polyphenol content ranged from 0.91 to 3.16 mg GAE/g in case of wheat loafs, and from 1.39 to 5.92 mg GAE/g in case of gluten-free loafs, while the total antioxidant content changed between 0.70 and 6.44 mg AAE/g in case of wheat loafs, and ranged from 2.55 to 9.75 in case of gluten-free loafs. Graphic abstract: [Figure not available: see fulltext.]

Open Access: Yes

DOI: 10.1007/s11696-021-01754-0

Case study on the tactical level of an autonomous vehicle control

Claudiu Radu Pozna Csaba Antonya Erno Horváth

Publication Name: International Conference on Electrical Computer Communications and Mechatronics Engineering Iceccme 2021

Publication Date: 2021-10-07

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

In this paper, a case study is presented on the tactical level of autonomous vehicle control. Inspired by the human driver behavior, vehicle control is structured in a hierarchy on three levels: the strategic, the tactical, and the operational level. These are connected by specific links, and based on prior information and models, are transforming the input data from the environment into actuator commands on the various degree of freedom of the vehicle. The case study is presenting a simulation of a scenario, detailing the vehicle models with sensors, the collection of behavior, and the behavior selector.

Open Access: Yes

DOI: 10.1109/ICECCME52200.2021.9590868

Application of spatio-temporal data in site-specific maize yield prediction with machine learning methods

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

Publication Name: Precision Agriculture

Publication Date: 2021-10-01

Volume: 22

Issue: 5

Page Range: 1397-1415

Description:

In order to meet the requirements of sustainability and to determine yield drivers and limiting factors, it is now more likely that traditional yield modelling will be carried out using artificial intelligence (AI). The aim of this study was to predict maize yields using AI that uses spatio-temporal training data. The paper has advanced a new method of maize yield prediction, which is based on spatio-temporal data mining. To find the best solution, various models were used: counter-propagation artificial neural networks (CP-ANNs), XY-fused Querynetworks (XY-Fs), supervised Kohonen networks (SKNs), neural networks with Rectangular Linear Activations (ReLU), extreme gradient boosting (XGBoost), support-vector machine (SVM), and different subsets of the independent variables in five vegetation periods. Input variables for modelling included: soil parameters (pH, P2O5, K2O, Zn, clay content, ECa, draught force, Cone index), micro-relief averages, and meteorological parameters for the 63 treatment units in a 15.3 ha research field. The best performing method (XGBoost) reached 92.1% and 95.3% accuracy on the training and the test sets. Additionally, a novel method was introduced to treat individual units in a lattice system. The lattice-based smoothing performed an additional increase in Area under the curve (AUC) to 97.5% over the individual predictions of the XGBoost model. The models were developed using 48 different subsets of variables to determine which variables consistently contributed to prediction accuracy. By comparing the resulting models, it was shown that the best regression model was Extreme Gradient Boosting Trees, with 92.1% accuracy (on the training set). In addition, the method calculates the influence of the spatial distribution of site-specific soil fertility on maize grain yields. This paper provides a new method of spatio-temporal data analyses, taking the most important influencing factors on maize yields into account.

Open Access: Yes

DOI: 10.1007/s11119-021-09833-8