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International Review of Applied Sciences and Engineering
Authors:
Éva Bácsné Bába
,
György Norbert Szabados
,
Szabolcs Gergely Orbán
,
Zoltán Bács
,
Renátó Balogh
, and
Sándor Kovács

Abstract

Many sports organisations operate as non-profits, but the emphasis and role of for-profits in this sector cannot be avoided. Today, sports activities are connected to the business sector and generate profit, hence, sports sector is a decisive part of the economy. Sport profile companies differ in their organisational strategy formulation approach. The main focus was to learn more about their strategy approach and market behaviour. 350 sports business organisations were involved in a survey of 3,248 companies, and the Chi-square test, variance analysis, and principal component analysis were applied to the sample. Results showed that 75.7% of the responding sports companies had no written strategic plan. The availability of written strategies seemed to depend on the organisation's scale. The market-following behaviour was confirmed in the case of smaller sports enterprises. Fitness service providers appeared to follow a market-leading behaviour. Growth, investment, and development naturally emerged as essential factors for companies with higher sales revenue and operating sports facilities, and they were relatively less important in sports goods production and trade. Most of the results showed that in the sports business sector, large-scale organisations focus on strategic-related issues more than other players in the industry.

Open access

Abstract

One critical issue in the tracking systems based on photovoltaic (PV) is how to harvest highest power of the photovoltaic array; particularly when the system is operating in partially shaded conditions (PSCs) or varying irradiances. This study proposes particle swarm optimization (PSO) hybridization and cuckoo search algorithm (CSA) methods for maximum power point tracking (MPPT). The effectiveness of the proposed algorithm is validated and examined under various irradiance patterns. A comparison study in performance has been conducted between the proposed hybrid CSA-PSO method with the conventional P&O and PSO techniques. Several tests have been performed based on numerical simulations utilizing the programming software MATLAB/Simulink. The results demonstrated that the suggested hybrid technique yields smaller tracking time, higher power and greater efficiency than those of other traditional algorithms.

Open access

Abstract

Composite materials are vulnerable to impacts that may occur during their use. Such transverse loads represent a significant threat to these materials because they can cause damage that is difficult to detect. Thus, understanding the mechanical behavior of composite materials during impacts is crucial for improving their damage resistance. Therefore, this study investigates the response of two commonly used composite panels in maritime transportation—a PVC core sandwich composite and a laminated GFRP composite—under quasi-static indentation (QSI). Using numerical simulations with Abaqus/Explicit, this investigation aims to anticipate mechanical characteristics and damage patterns during low-velocity impact. Results show a strong correlation between numerical and experimental data. The force-displacement curves aid in understanding damage sequences, with predicted maximum loads at 1.43% and 6.45% accuracy for laminated and sandwich composites. Both exhibit significant damage, including permanent indentation, matrix cracks, fiber fractures, and prevalent delamination around the impact point.

Open access

Abstract

This study evaluates metallic yield dampers, specifically slit steel dampers, for protecting steel beam-to-column connections during seismic events. Finite element model simulations were conducted for the damper and its connection. Analysis of circular parameters, like the radius slot, showed that appropriately sized slit dampers exhibit advantageous seismic behavior. Moment-rotation, hysteresis curves, and plastic stresses comparisons indicate efficient energy absorption. The maximum moment was 25% lower than conventional samples. The slit steel damper model with a ductility factor of 3.5 allows significant plastic deformation before potential failure. Results emphasize the slit damper's potential for optimal performance in steel frames, suggesting its use for efficient energy absorption.

Restricted access

Abstract

Geopolymer concrete (GPC) is a rising eco-conscious substitute for traditional cement-based concrete, bringing the construction industry closer to sustainability. Self-compacting geopolymer concrete (SCGC) enhances the concrete flowability and fills the congested reinforced areas without vibrators in concrete structures such as bridges, tunnels and canals. This study aims to analyze the impact of silicon dioxide nanoparticles (NS) on the rheological and mechanical properties of SCGC to optimize the dosage of NS in SCGC. For this purpose, NS (0–6%) blended in partially distributed binders of fly ash and ground granulated blast furnace slag (50:50) with 0.5 alkaline binder ratio, 2% superplasticizers (9 kg m−3) (MasterGlenium SKY 8233) and 12% extra water (54 kg m−3). Sodium silicate solution and sodium hydroxide ratio of 2.5 was used for this study. It is observed that SCGC with 3% NS replacement complied with the guidelines of EFNARC. According to the T50cm slump flow test, V-funnel test, and L-box test results meet the guidelines of up to 4% NS replacement, and 3% NS addition offers excellent mechanical properties in SCGC. This study concluded that the replacement of 3% of NS improved the fresh and hardened properties of SCGC, which can apply to construction.

Open access

Abstract

Today, the role of humans is changing rapidly in both industrial production activities and services. Mediocre, easy-to-learn activities can be performed more efficiently by machines; mediocre knowledge is being devalued while the importance of high-level skills is increasing. As a result, in all sectors of the economy, and especially in engineering, new approaches to expert training are needed; people must learn to hand over certain decision-making roles and to control the processes supported by AI rather than compete with it. STEM education has a responsibility to achieve these goals and must develop appropriate tools for engineering education. This paper presents a complex didactic methodology for competency-based education in engineering bachelor programs. An important element is the mathematical competency map, which shows the importance and place of mathematical and algorithmic (coding) knowledge in engineering topics. Another element is the systematic testing of mathematical knowledge in non-mathematical contexts in engineering courses. We provide an overview of our achievements in applying the developed toolset and improving the efficiency of mathematics teaching in engineering bachelor programs.

Open access
Pollack Periodica
Authors:
Mahmood Alhafadhi
,
Masar Alsigar
,
Oudah Zahraa A.
,
Zoltán Bézi
,
Alden abd alal Sahm
, and
P. Ravinder Reddy

Abstract

Using finite element methods, residual stresses were estimated in pipe welds. Experiments were also conducted to verify the numerical results. An alternative to a three-dimensional model was used to simplify the numerical calculation for residual stresses investigation. Model predictions were validated by measuring residual stresses using X-ray diffraction. As compared to measured residual stress distributions, the computational approaches developed in this study can accurately predict welding residual stress distributions. The focused welding parameters have a significant impact on residual stresses even when all the other parameters are the same.

Restricted access

Abstract

The predictive maintenance of permeant magnet synchronous motor is highly required as this kind of motor has been commonly employed in electric vehicles, industrial systems, and other applications owing to its high power density output, as well as the regenerative operation characteristics during braking and deceleration driving conditions. One of the most important causes of PMSM failure is the stator short and drive switches failure. These problems have attracted more attention in the field of deep learning for fault detection purposes in the early stages, to avoid any system breakdown, and to decrease the risk and price of maintenance. In this paper, we investigate the possibility of detecting the electrical faults in PMSM by generating our data which includes current signals that have been analyzed and preprocessed by applying Continuous Wavelet Transform (CWT) to select the reliable features this conversion will be used to train ResNet 50. The evaluation metrics have shown that ResNet 50 achieves an accuracy of 100% for the classification of faults.

Open access

Assessing Novel Fiber Reinforcement Against Conventional Mix by Using Both Natural and Synthetic Fibers in Concrete with Statistical Performance Analysis

A természetes és szintetikus szálak felhasználásával készülő szálerősítésű és a hagyományos beton keverékek összehasonlítása, értékelése és statisztikai elemzése

Építés - Építészettudomány
Authors:
Vijayan Selvam
and
Tholkapiyan Muniyandi

This research investigates the effect of incorporating innovative human hair fibers (HHF) and polypropylene fibers (PPF) into concrete, which has been observed to enhance the material’s strength characteristics. These fibers augment the concrete’s tensile strength and resilience, fortifying it against cracks and elevating its overall endurance. This research delves into the impact of reinforcing concrete specimens with human hair and polypropylene fibers. These specimens are employed in cube, cylinder and flexural beam tests. Both fresh and hardened properties, such as compaction factor and slump, and compressive, split-tensile, and flexural strength at varying curing periods (28 days and 90 days) and the ratios (1%, 2%, and 3%) are considered by weight of cement. Specifically, the 3% polypropylene fiber concrete mix exhibited the highest average compressive strength at both 28 and 90 days, while the 2% polypropylene fiber mix showed the highest split-tensile strength. Flexural strength results followed a similar trend. Results show that 3% HHF addition leads to notable improvements in concrete strength properties, albeit not as significant as with polypropylene fibers. Statistical analysis, including independent samples Kruskal–Wallis tests, was conducted to compare the distributions of strength values across different groups. The statistical analysis indicates significant differences in strength distributions across groups, with p-values below the significance level of 0.05. This underscores HHF’s potential as a sustainable alternative in construction applications, contributing to enhanced concrete strength.

Restricted access
Pollack Periodica
Authors:
Peter Ivanyi
,
Amalia Ivanyi
,
Aarne Jutila
,
Jenő Balogh
,
Barry H. V. Topping
, and
Gabriella Medvegy
Open access