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Publications - 6374

Cognitive Classifier of Hand Gesture Images for Automated Sign Language Recognition: Soft Robot Assistance Based on Neutrosophic Markov Chain Paradigm

Áron Ballagi Oday Ali Hassen Saad M. Saad Muslem Al-Saidi

Publication Name: Computers

Publication Date: 2024-04-01

Volume: 13

Issue: 4

Page Range: Unknown

Description:

In recent years, Sign Language Recognition (SLR) has become an additional topic of discussion in the human–computer interface (HCI) field. The most significant difficulty confronting SLR recognition is finding algorithms that will scale effectively with a growing vocabulary size and a limited supply of training data for signer-independent applications. Due to its sensitivity to shape information, automated SLR based on hidden Markov models (HMMs) cannot characterize the confusing distributions of the observations in gesture features with sufficiently precise parameters. In order to simulate uncertainty in hypothesis spaces, many scholars provide an extension of the HMMs, utilizing higher-order fuzzy sets to generate interval-type-2 fuzzy HMMs. This expansion is helpful because it brings the uncertainty and fuzziness of conventional HMM mapping under control. The neutrosophic sets are used in this work to deal with indeterminacy in a practical SLR setting. Existing interval-type-2 fuzzy HMMs cannot consider uncertain information that includes indeterminacy. However, the neutrosophic hidden Markov model successfully identifies the best route between states when there is vagueness. This expansion is helpful because it brings the uncertainty and fuzziness of conventional HMM mapping under control. The neutrosophic three membership functions (truth, indeterminate, and falsity grades) provide more layers of autonomy for assessing HMM’s uncertainty. This approach could be helpful for an extensive vocabulary and hence seeks to solve the scalability issue. In addition, it may function independently of the signer, without needing data gloves or any other input devices. The experimental results demonstrate that the neutrosophic HMM is nearly as computationally difficult as the fuzzy HMM but has a similar performance and is more robust to gesture variations.

Open Access: Yes

DOI: 10.3390/computers13040106

A novel approach of quenchant evaluation by applying quality functions

Imre Czinege B. Smoljan Imre Felde Rafael Colas

Publication Name: Materials Science Forum

Publication Date: 2007-01-01

Volume: 537-538

Issue: Unknown

Page Range: 513-518

Description:

A novel numerical approach for testing and evaluation of quenching media and quenching systems is outlined. The technique proposed is based on determination of heat transfer coefficient from temperature signals recorded and applying it as input for simulation of quenching process. The evaluation method is based on the calculated microstructural and mechanical properties of cylindrical samples.

Open Access: Yes

DOI: 10.4028/0-87849-426-x.513

Toward Sustainable 3D Printing: Tensile Mechanical Comparison of PLA/PBAT Biopolymer Blend and TPU in MEX Additive Manufacturing †

László Lendvai Sándor K. Jakab

Publication Name: Engineering Proceedings

Publication Date: 2025-01-01

Volume: 113

Issue: 1

Page Range: Unknown

Description:

A biopolymer blend of poly(lactic acid) (PLA) and poly(butylene adipate-co-terephtalate) (PBAT) in a 60/40 weight ratio was investigated as a potential green alternative to thermoplastic polyurethane (TPU) for material extrusion (MEX)-based additive manufacturing. A comparison of the two materials was conducted based on their tensile mechanical properties, evaluated using 3D-printed specimens fabricated with three distinct infill raster orientations (0°, ±45°, and 90°). The results showed that the tensile strengths of the two materials were relatively similar, ranging from 14.7 to 34.8 MPa, depending on the raster angle. However, the stiffness of PLA/PBAT was considerably higher than that of TPU, as reflected by Young’s modulus values an order of magnitude greater. While the elongation at break was comparable at 0° infill orientation (214% for PLA/PBAT and 265% for TPU), TPU exhibited better tolerance to increasing raster angles, with elongation only decreasing to 134% at 90°. In contrast, PLA/PBAT dropped drastically to 2%.

Open Access: Yes

DOI: 10.3390/engproc2025113022

Optimal Plastic Reliable Design of Reinforced Concrete Beams Considering Steel Bars Volume Probability

Majid Movahedi Rad Sarah Khaleel Ibrahim

Publication Name: Mathematics

Publication Date: 2023-05-01

Volume: 11

Issue: 10

Page Range: Unknown

Description:

This paper aims to investigate the plastic response of reinforced concrete tapered beams when subjected to random steel reinforcement volumes, using both deterministic and probabilistic analyses, with the complementary strain energy as a boundary in the first case, and the reliability index as a boundary in the second. The first step in this study was to use a previously studied model and perform a deterministic analysis, assuming that the complementary strain energy is a limiting factor and controller of the plastic behaviour. Next, a probabilistic analysis is applied, with the reliability index as a limitation. At the same time, the volume of the reinforcement steel used, and the complementary strain energy were treated as probabilistic variables with mean values and specific standard deviations. This novel method highlighted the plastic behaviour limiting procedure and provided results that highlighted the nature of the model’s changed behaviour when the complementary strain energy was controlled and when applying probabilistic properties with reliability index limitation.

Open Access: Yes

DOI: 10.3390/math11102349

Speed sensorless field oriented control of induction machines using unscented kalman filter

Krisztian Horvath Marton Kuslits

Publication Name: Proceedings 2017 International Conference on Optimization of Electrical and Electronic Equipment Optim 2017 and 2017 Intl Aegean Conference on Electrical Machines and Power Electronics Acemp 2017

Publication Date: 2017-07-11

Volume: Unknown

Issue: Unknown

Page Range: 523-528

Description:

In this paper, an observer-based speed sensorless field oriented control (FOC) algorithm is presented for induction machines. The state observer is based on a new, detailed observer model which describes the machine with seven state variables, i.e. with seven equations. Since these equations are strongly non-linear, the applied observer algorithm is the unscented Kalman filter (UKF). Using the advantages of the detailed non-linear model and the UKF algorithm, the state variables can be estimated adequately, including the rotor flux position. Using these variables a speed sensorless FOC structure has been developed.

Open Access: Yes

DOI: 10.1109/OPTIM.2017.7975021

First report of the genus Bostocktrachys Hirschmann, 1979 from India (Acari, Mesostigmata, Uropodina, Trachyuropodidae) with the description of a new species and with note to the ontogeny of the genus

Sergey G. Ermilov Jenő Kontschán

Publication Name: Ecologica Montenegrina

Publication Date: 2024-01-01

Volume: 78

Issue: Unknown

Page Range: 235-242

Description:

The first representatives of the genus Bostocktrachys Hirschmann, 1979 have been discovered in India and are described here as Bostocktrachys wisniewskii sp. nov. based on females, males and nymphs. The new species differs from its congeners on the basis of the shape of grooves on the dorsal shields, dorsal and ventral setae and dorsal and ventral culptural pattern. The second deutonymph and the first protonymph of this genus are presented and discussed.

Open Access: Yes

DOI: 10.37828/em.2024.78.22

Mechanism of directed technological investment on energy productivity and energy structure: A unified theoretical framework

Yee Van Fan Xiaojun Sun Yalin Lei Ting Pan Petar Sabev Varbanov

Publication Name: Energy Economics

Publication Date: 2024-12-01

Volume: 140

Issue: Unknown

Page Range: Unknown

Description:

The mechanisms and effects of technological investment on energy productivity and energy structure in the petrochemical industry remain unclear due to the directional nature of technological progress. This study proposes a unified theoretical framework for the impact of directed technological investment on energy productivity and energy structure by incorporating energy factors into the theory of technological progress bias. The aim is to elucidate the impact of technological progress on energy productivity and energy structure, and to unravel the underlying effect mechanisms. A fixed effects model that includes moderating effects is also developed to support the assessment. The study found that the petrochemical industry's technological investment in China was initially biased towards enhancing labour-augmenting technological progress. The mechanism analysis revealed that technological investment, under the moderating effects of price and environmental governance, preferred a capital-energy bias, leading to insignificant improvements in energy productivity but a substantial increase in labour productivity. In addition, the technological investment, influenced by the moderating effect of environmental governance, led to some improvement in the energy structure during the sample period. This study integrates the mechanisms of directed technological investment on energy productivity and energy structure into a unified analytical framework, systematically investigating the reasons, effect mechanisms, and consequences of bias, while providing empirical evidence that supports low-carbon development in the petrochemical industry.

Open Access: Yes

DOI: 10.1016/j.eneco.2024.107943

Evaluation of Local Planner-Based Stanley Control in Autonomous RC Car Racing Series

Gergely Bári Máté Fazekas János Tóth Zalán Demeter Ármin Bogár-Németh

Publication Name: IEEE Intelligent Vehicles Symposium Proceedings

Publication Date: 2024-01-01

Volume: Unknown

Issue: Unknown

Page Range: 252-257

Description:

This paper proposes a control technique for autonomous RC car racing. The presented method does not require any map-building phase beforehand since it operates only local path planning on the actual LiDAR point cloud. Racing control algorithms must have the capability to be optimized to the actual track layout for minimization of lap time. In the examined one, it is guaranteed with the improvement of the Stanley controller with additive control components to stabilize the movement in both low and high-speed ranges, and with the integration of an adaptive lookahead point to induce sharp and dynamic cornering for traveled distance reduction. The developed method is tested on a 1/10-sized RC car, and the tuning procedure from a base solution to the optimal setting in a real F1Tenth race is presented. Furthermore, the proposed method is evaluated with a comparison to a more simple reactive method, and in parallel to a more complex optimization-based technique that involves offline map building the global optimal trajectory calculation. The performance of the proposed method compared to the latter, referring to the lap time, is that the proposed one has only 8% lower average speed. This demonstrates that with appropriate tuning, a local planning-based method can be comparable with a more complex optimization-based one. Thus, the performance gap is lower than 10% from the state-of-the-art method. Moreover, the proposed technique has significantly higher similarity to real scenarios, therefore the results can be interesting in the context of automotive industry.

Open Access: Yes

DOI: 10.1109/IV55156.2024.10588629

Enhancing urban solar photovoltaic system performance evaluation through a disc spherical fuzzy aggregation framework

Nebojsa Bacanin Dragan Pamucar Shahzaib Ashraf Muhammad Shakir Chohan Wania Iqbal Vladimir Simic

Publication Name: Journal of Computational Science

Publication Date: 2026-01-01

Volume: 93

Issue: Unknown

Page Range: Unknown

Description:

The integration of solar photovoltaic (PV) systems in urban environments promises great potential for sustainable energy applications. However, the unique characteristics of cities, the varieties of weather that occur at the place, and technology inefficiency make performance evaluation difficult. This paper sought to address the pressing need for a robust performance evaluation framework for urban solar PV systems by developing a disc spherical fuzzy aggregation framework. It develops basic algebraic aggregation operations in the framework of the disc spherical fuzzy set (D-SFSs), proving their completeness and describing their essential characteristics. These new operators conceived to operate on D-SFSs furnish theoretical robustness and provide the foundation for decisions made. A shining novel disc spherical fuzzy method is developed namely combinative distance-based assessment (CODAS) in D-SFS. A case study regarding the application of this model in the assessment of performance by urban solar PV systems is being conducted, thus proving the application aspect. Results come out positive in interpreting the decision-making dilemma and differences among several experts. This would, therefore, encourage various sectors to expand the use of D-SFSs in decision support systems and similar areas by showing how useful they can be in actual situations.

Open Access: Yes

DOI: 10.1016/j.jocs.2025.102758