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Epoxy resins are widely used in a variety of engineering applications, including composite wind turbine blades used in the renewable energy industry, highly complex structural components for aircraft, paints, coatings, industrial tooling, biomedical systems, adhesives, electronics and automotive. Epoxies' low fracture toughness is one of the key obstacles preventing its adoption in a wider range of applications. To address epoxy's low fracture toughness, this paper aims to examine the roles of intra-ply hybridization and nano reinforcing.

This paper investigates the role of intra-ply hybridization of glass-carbon woven fibers and adding 0.8 wt.% of multiwall carbon nanotube (MWCNT) nano reinforcement to overcome the low fracture toughness of epoxy. A bending test is used to calculate the composites elastic parameters, and a notched sample three-point bending test is used to show crack behavior in addition to using materials characterization methods to reveal the effect of the MWCNT on structure, bonding, glass transition temperature (Tg) and dispersion of MWCNT in the matrix. Furthermore, this paper suggests using the finite element method to overcome the difficulty in calculating the crack extension.

Intra-ply hybridization and MWCNT reinforcement decrease the crack extension of epoxy with time. The inclusion of high-strength carbon fiber increased the fracture toughness of glass composite. Furthermore, the existence of MWCNT in the surrounding area of the notch in epoxy composites hinders crack propagation and provides stiffness at the interface by bridging the crack and eventually enhancing its fracture toughness.

Studying the role of intra-ply hybridization of glass-carbon woven fibers and adding 0.8 wt.% of MWCNT nano reinforcement to overcome the low fracture toughness of epoxy. Additionally, this research recommends using the finite element method to overcome the challenge of computing the crack extension.

Various designs of corrugated webs include trapezoidal, sinusoidal, triangular and rectangular profiles. The increasing use of curved plates has prompted the creation of I-sections made of steel with a corrugated web design. This study aims to examine the effectiveness of an I-beam steel section that features a perforated-triangular web profile.

In the current study, finite element analysis was conducted on corrugated-perforated steel I-sections using ANSYS software. The study focused on inspecting the design of the perforations, including their shape (circle, square, hexagon, diamond and octagon), size of perforations (80 mm, 100 mm and 120 mm) and layout (the position of web perforation), as well as examining the geometric properties of the section in term of bending, lateral torsional buckling, torsion and shear behavior.

The study revealed that perforations with diamond, circle and hexagon shapes exhibit good performance, whereas the square shape performs poorly. Moreover, the steel section’s performance decreases with an increase in perforation size, regardless of loading conditions. In addition, the shape of the web perforations can also influence its stress distribution. For example, diamond-shaped perforations have been found to perform better than square-shaped perforations in terms of stress distribution and overall performance. This was because of their ability to distribute stress more evenly and provide greater support to the surrounding material. The diagonal alignment of the diamond shape aligns with principal stress directions, allowing for efficient load transfer and reduced stress concentrations. Additionally, diamond-shaped perforations offer a larger effective area, better shear transfer and improved strain redistribution, resulting in enhanced structural integrity and increased load-carrying capacity.

Hence, the presence of lateral-torsional buckling and torsional loading conditions significantly impacts the performance of corrugated-perforated steel I-sections.

To prevent the coil from burning or getting damaged, it is necessary to estimate the duration of its operation as long as its temperature does not exceed the permissible limit. This paper aims to investigate the effect of switching on the thermal behavior of impregnated and nonimpregnated windings. Also, the safe operating time for each winding is determined.

The power loss of the winding is expressed as a function of the winding specifications. Using homogenization techniques, the equivalent thermal properties for the homogenized winding are calculated and used in a proposed thermal equivalent circuit for winding modeling and analysis. The validity and accuracy of the proposed model are determined by comparing its analysis results and simulation and measurement results.

The results show that copper windings have better thermal behavior and lower temperature compared to aluminum windings. On the other hand, by impregnating or increasing the packing factor of the winding, the thermal behavior is improved. Also, by choosing the right duty cycle for the winding current source, it is possible to prevent the burning or damage of the winding and increase its lifespan. Comparing the measurement results with the analysis results shows that the proposed equivalent circuit has an error of less than 4% in the calculation of the winding center temperature.

In this paper, the effect of temperature on the electrical resistance of the coil is ignored. Also, rectangular wires were not investigated. Research in these topics are considered as future work.

By calculating the thermal time constant of the winding, its safe operation time can be calculated so that its temperature does not exceed the tolerable value (150 °C). The proposed method analyzes both impregnated and nonimpregnated windings with various schemes. It investigates the effects of switching on their thermal behavior. Additionally, it determines the safe operating time for each type of winding.

Wire-arc-based additive manufacturing (WAAM) is a promising technology for the efficient and economical fabrication of medium-large components. However, the anisotropic behavior of the multilayered WAAM-fabricated components remains a challenging problem.

The purpose of this paper is to conduct a comprehensive study of the grain morphology, crystallographic orientation and texture in three regions of the WAAM printed component. Furthermore, the interdependence of the grain morphology in different regions of the fabricated component with their mechanical and tribological properties was established.

The electron back-scattered diffraction analysis of the top and bottom regions revealed fine recrystallized grains, whereas the middle regions acquired columnar grains with an average size of approximately 8.980 µm. The analysis revealed a higher misorientation angle and an intense crystallographic texture in the upper and lower regions. The investigations found a higher microhardness value of 168.93 ± 1.71 HV with superior wear resistance in the bottom region. The quantitative evaluation of the residual stress detected higher compressive stress in the upper regions. Evidence for comparable ultimate tensile strength and greater elongation (%) compared to its wrought counterpart has been observed.

The study found a good correlation between the grain morphology in different regions of the WAAM-fabricated component and their mechanical and wear properties. The Hall–Petch relationship also established good agreement between the grain morphology and tensile test results. Improved ductility compared to its wrought counterpart was observed. The anisotropy exists with improved mechanical properties along the longitudinal direction. Moreover, cylindrical components have superior tribological properties compared with cuboidal components.

This paper aims to investigate the influence of “BroncoCut-X” (copper core-ZnCu50 coating) electrode on the machining of Ti-3Al-2.5V in view of its extensive use in aerospace and medical applications. The machining parameters are selected as Spark-off Time (ST_off), Spark-on Time (ST_on), Wire-speed (S_w), Wire-Tension (WT) and Servo-Voltage (S_v) to explore the machining outcomes. The response characteristics are measured in terms of material removal rate (MRR), average kerf width (KW) and average-surface roughness (SA).

Taguchi’s approach is used to design the experiment. The “AC Progress V2 high precision CNC-WEDM” is used to conduct the experiments with ϕ 0.25 mm diameter wire electrode. The machining performance characteristics are examined using main effect plots and analysis of variance. The grey-relation analysis and fuzzy interference system techniques have been developed to combine (called grey-fuzzy reasoning grade) the experimental response while Rao-Algorithm is used to calculate the optimal performance.

The hybrid optimization result is obtained as ST_off = 50µs, ST_on = 105µs, S_w = 7 m/min, WT = 12N and S_v=20V. Additionally, the result is compared with the firefly algorithm and improved gray-wolf optimizer to check the efficacy of the intended approach. The confirmatory test has been further conducted to verify optimization results and recorded 8.14% overall machinability enhancement. Moreover, the scanning electron microscopy analysis further demonstrated effectiveness in the WEDMed surface with a maximum 4.32 µm recast layer.

The adopted methodology helped to attain the highest machinability level. To the best of the authors’ knowledge, this work is the first investigation within the considered parametric range and adopted optimization technique for Ti-3Al-2.5V using the wire-electro discharge machining.

This paper aims to investigate how best to classify money laundering through online video games (i.e. virtual laundering). Currently, there is no taxonomy available for scholars and practitioners to refer to when discussing money laundering through online video games. Without a well-defined taxonomy it becomes difficult to reason through, formulate and implement effective regulatory measures, policies and security controls. As such, efforts to prevent and reduce virtual laundering incidence rates are hampered.

This paper proposes three mutually exclusive virtual laundering categorizations. However, instead of fixating on the processes undergirding individual instances of virtual laundering, it is argued that focusing on the initial locale of the illicit proceeds provides the appropriate framing within which to classify instances of virtual laundering. Thus, the act of classification becomes an ontological endeavour, rather than an attempt at elucidating an inherently varied process (as is common of the placement, layering and integration model).

A taxonomy is proposed that details three core virtual laundering processes. It is demonstrated how different virtual laundering categories have varied levels of associated risk, and thus, demand unique interventions.

To the best of the authors’ knowledge, this is the first taxonomy available in the knowledge base that systematically classifies instances of virtual laundering. The taxonomy is available for scholars and practitioners to use and apply when discussing how to regulate and formulate legislation, policies and appropriate security controls.

The purpose of this paper is to investigate the effect of NaCl solution with different concentrations on impact-sliding fretting corrosion behavior of Inconel 690TT steam generator heat transfer tubes.

The optical 3D profiler was used to measure the wear profile and calculated the wear volume. Corrosion behavior was studied using open circuit potential monitoring and potentiodynamic polarization testing. The morphologies and elemental distributions of wear scars were analyzed using scanning electron microscopy and energy-dispersive spectroscopy. The synergism of wear and corrosion was analyzed according to the ASTM G119 standard.

The corrosion tendency reflected by OCP and the corrosion current calculated by Tafel both increased with the increase of NaCl concentration. The total volume loss of the material increased with concentration, and it was known from the synergism that the volume loss caused by corrosion-enhanced wear accounted for the largest proportion, while the wear-enhanced corrosion also made a greater contribution to volume loss than tangential fretting corrosion. Through the analysis of the material morphologies and synergism of wear and corrosion, the damage mechanism was elucidated.

The research findings can provide reference for impact-sliding fretting corrosion behavior of Inconel 690TT heat transfer tubes in NaCl solution with different concentrations.

The primary purpose of this exploratory paper is to propose a novel analytical framework for examining corruption from a behavioral perspective by highlighting multiple issues associated with consumerism.

This paper examines the relationship between excessive consumption activities and corrupt acts, drawing upon existing literature on corruption, consumerism and consumption, as well as multiple reports and cases of corruption and money laundering in Indonesia. With regard to corruption networks, this paper analyses the associated behavioral patterns and social dynamics by using the Fraud Triangle and the Fraud Elements Triangle frameworks to examine the phenomenon of living beyond one’s means. This paper also addresses the notion of sacredness in the context of consumer activities and how such sacredness plays a role in causing otherwise honest individuals to engage in corrupt acts.

The author established that corruption represents a complex societal issue that extends across several dimensions of society, encompassing both horizontal and vertical aspects. Consequently, addressing this problem poses significant challenges. Excessive consumption has been identified as one of the various behavioral concerns that are implicated in the widespread occurrence of corruption in many nations. Individuals who partake in excessive consumption play a role in shaping ethical norms that serve to legitimize and rationalize immoral behavior, therefore fostering a society marked by corruption. The act of engaging in excessive consumption is also associated with cases of money laundering offenses that are connected to corruption and several other illicit activities. The lifestyle of corrupt individuals is one of the primary behavioral concerns associated with corruption, as “living beyond means” is the most common behavioral red flag among occupational fraud offenders worldwide. The phenomenon of consumerism may also shape the minds of individuals as if it were an “implicit religion” due to the fact that it may generate human experiences that elicit highly positive emotions and satisfy certain sacredness-associated characteristics. The pursuit of transcendental experiences through the acquisition and consumption of sacred consumption objects may heighten the incentive to commit fraudulent acts such as corruption.

This self-funded exploratory study uses document analysis to examine the corruption phenomenon in Indonesia. Future studies will benefit from in-depth interviews with former offenders and investigators of corruption.

This exploratory study contributes to advancing corruption prevention strategies. It does this by introducing a novel analytical framework that allows for the examination of several behavioral issues associated with consumerism, which have the potential to foster the proliferation of corruption.

This exploratory study highlights the importance of comprehending the intricacies of consumerism, namely, its adverse effects on the proliferation of corruption.

This Friction stir welding study aims to weld thick AA8011 aluminium plates, and the interface joints created with a variety of tool pin profiles were examined for their effects on the welding process.

Scanning electron microscopy and optical microscopy and X-ray diffraction were used to examine the macro and micro-structural characteristics, as well as the fracture surfaces, of tensile specimens. The mechanical properties (tensile, hardness tests) of the base metal and the welded specimens under a variety of situations being tested. Additionally, a fracture toughness test was used to analyse the resilience of the base metal and the best weldments to crack formation. Using a response surface methodology with a Box–Behnken design, the optimum values for the three key parameters (rotational speed, welding speed and tool pin profile) positively affecting the weld quality were established.

The results demonstrate that a defect-free junction can be obtained by using a cylindrical tool pin profile, increasing the rotational speed while decreasing the welding speeds. The high temperature and compressive residual stress generated during welding leads to the increase in grain size. The grain size of the welded zone for optimal conditions is significantly smaller and the hardness of the stir zone is higher than the other experimental run parameters.

The work focuses on the careful examination of microstructures behaviour under various tool pin profile responsible for the change in mechanical properties. The mathematical model generated using Taguchi approach and parameters was optimized by using multi-objectives response surface methodology techniques.

The study integrated understanding by design-Internet of Things (UbD-IoT) education with design thinking and computational thinking to plan and design an IoT course. Cross-domain application examples were employed to train students in problem-understanding, deep thinking and logical design for IoT applications.

In this study, the UbD model was integrated with design thinking and computational thinking in the planning and design of an IoT course. The examples of cross-domain applications were used to train students to understand a problem by engaging themselves in deep thinking and helping them think and design logically for an IoT application.

The UbD-IoT learning design greatly decreased students' overall cognitive load. UbD-IoT learning has a significant impact on the performance of computational thinking in problem-solving and problem-understanding. The impact of UbD-IoT learning on logical thinking and program learning cognition in students needs to be verified.

The results of this study have shown that the UbD model is effective in reducing the cognitive load of a learning course and also strengthens T-competencies in the lateral skills of computational thinking, critical problem-solving, logical thinking and creative thinking.