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The aim of this study is to determine the fracture behavior of wool felt and fabric based epoxy composites and their responses to electromagnetic waves.

Notched and unnotched tensile tests of composites made of wool only and hybridized with a glass fiber layer were carried out, and fracture behavior and toughness at macro scale were determined. They were exposed to electromagnetic waves between 8 and 18 GHz frequencies using two horn antennas.

The keratin and lignin layer on the surface of the wool felt caused lower values to be obtained compared to the mechanical values given by pure epoxy. However, the use of wool felt in the symmetry layer of the laminated composite material provided higher mechanical values than the composite with glass fiber in the symmetry layer due to the mechanical interlocking it created. The use of wool in fabric form resulted in an increase in the modulus of elasticity, but no change in fracture toughness was observed. As a result of the electromagnetic analysis, it was also seen in the electromagnetic analysis that the transmittance of the materials was high, and the reflectance was low throughout the applied frequency range. Hence, it was concluded that all of the manufactured materials could be used as radome material over a wide band.

Sheep wool is an easy-to-supply and low-cost material. In this paper, it is presented that sheep wool can be evaluated as a biocomposite material and used for radome applications.

The combined evaluation of felt and fabric forms of a natural and inexpensive reinforcing element such as sheep wool and the combined evaluation of fracture mechanics and electromagnetic absorption properties will contribute to the evaluation of biocomposites in aviation.

Composite materials have revolutionized the aerospace industry by offering superior structural qualities over traditional elements. This study aims to focus on the development and testing of bamboo natural fiber-based composites enhanced with SiO₂ nanoparticles.

The investigation involved fabricating specimens with varying nanoparticle compositions (0, 10 and 20%) and conducting tensile, flexural, impact and fracture toughness tests. Results indicated significant improvements in mechanical properties with the addition of nanoparticles, particularly at a 10% composition level.

This study underscores the potential of natural fiber composites, highlighting their environmental friendliness, cost-effectiveness and improved structural properties when reinforced with nanoparticles. The findings suggest an optimal ratio for nanoparticle integration, emphasizing the critical role of precise mixing proportions in achieving superior composite performance.

The tensile strength, flexural strength, impact resistance and fracture toughness exhibited notable enhancements compared with the 0 and 20% nanoparticle compositions. The 10% composition showed the most promising outcomes, showcasing increased strength across all parameters.

This study aims to investigate the possible defects and their root causes in a soft-termination multilayered ceramic capacitor (MLCC) when subjected to a thermal reflow process.

Specimens of the capacitor assembly were subjected to JEDEC level 1 preconditioning (85 °C/85%RH/168 h) with 5× reflow at 270°C peak temperature. Then, they were inspected using a 2 µm scanning electron microscope to investigate the evidence of defects. The reliability test was also numerically simulated and analyzed using the extended finite element method implemented in ABAQUS.

Excellent agreements were observed between the SEM inspections and the simulation results. The findings showed evidence of discontinuities along the Cu and the Cu-epoxy layers and interfacial delamination crack at the Cu/Cu-epoxy interface. The possible root causes are thermal mismatch between the Cu and Cu-epoxy layers, moisture contamination and weak Cu/Cu-epoxy interface. The maximum crack length observed in the experimentally reflowed capacitor was measured as 75 µm, a 2.59% difference compared to the numerical prediction of 77.2 µm.

This work's contribution is expected to reduce the additional manufacturing cost and lead time in investigating reliability issues in MLCCs.

Despite the significant number of works on the reliability assessment of surface mount capacitors, work on crack growth in soft-termination MLCC is limited. Also, the combined experimental and numerical investigation of reflow-induced reliability issues in soft-termination MLCC is limited. These cited gaps are the novelties of this study.

Given the increasingly important role of knowledge capital on key outcomes and innovation capabilities of organizations, this paper aims to investigate the influences of knowledge-based human resource management (KHRM) practices on innovation capability of firms via mediating role of knowledge sharing (KS). This study also examines whether competitive intensity moderates the effects of KS behaviors on specific aspects of innovation capability, namely, product and process innovation.

This paper used structural equation modeling to examine the level of how KHRM practices and KS impact on two types of innovation capability, namely, product innovation and process innovation using data collected from 265 participants in 112 manufacturing and service firms in Vietnam.

The research findings confirm the mediating roles of KS behaviors between KHRM practices and two specific types of innovation. Besides, the paper first reveals the moderating role of competitive intensity in the relationships between KS and product innovation. The results underline the necessity of building a climate of KHRM practices to stimulate employees sharing knowledge, which, in turn, positively promotes innovation capabilities in an organization.

Future research should investigate the impact of different forms of human resource management (HRM) practices on innovation via the mediating effects of certain aspects of KS to bring better understanding on the importance of HRM practices and knowledge resources in pursuing innovation competence.

This paper offers leaders a deeper understanding of potential effects of competitive intensity and environmental factors to promote innovation capabilities in their firms.

This paper has significant contributed to theoretical and practical initiatives on theory of HRM practices and knowledge management by showing different moderating and mediating mechanism thereby firms can follow to enhance innovation capability of firms in developing and emerging markets.

The purpose of this study is to investigate the phenomenon of defensive biasing in work stress surveys, which occurs when employees trivialize potential stressors and strains due to fear of negative consequences from their supervisors or management. This study aims to better understand the factors that influence this behavior and to develop a scale to measure it.

The study used an online survey of 200 employees to investigate the factors influencing defensive biasing behavior. The researchers developed a scale for defensive biasing with the help of subject matter experts and derived possible factors from the literature. Participants were presented with a hypothetical scenario in which they imagined a work stress survey in their organization and were asked to answer related items. The data were analyzed using regression analysis.

The study found that defensive biasing behavior was significantly predicted by perceived anonymity and neuroticism. Participants who felt less anonymous and had higher levels of neuroticism were more likely to engage in defensive biasing. Job insecurity and trust in supervisors were not found to be significant predictors of defensive biasing.

This study contributes to the literature on work stress surveys by developing a scale for defensive biasing and investigating the factors that influence this behavior. The study highlights the importance of making the survey process more transparent to reduce defensive biasing and obtain trustworthy results.

Prefabricated columns connected by grouted sleeves are increasingly used in practical projects. However, seismic fragility analyses of such structures are rarely conducted. Seismic fragility analysis has an important role in seismic hazard evaluation. In this paper, the seismic fragility of sleeve connected prefabricated column is analyzed.

A model for predicting the seismic demand on sleeve connected prefabricated columns has been created by incorporating engineering demand parameters (EDP) and probabilities of seismic failure. The incremental dynamics analysis (IDA) curve clusters of this type of column were obtained using finite element analysis. The seismic fragility curve is obtained by regression of Exponential and Logical Function Model.

The IDA curve cluster gradually increased the dispersion after a peak ground acceleration (PGA) of 0.3 g was reached. For both columns, the relative displacement of the top of the column significantly changed after reaching 50 mm. The seismic fragility of the prefabricated column with the sleeve placed in the cap (SPCA) was inadequate.

The sleeve was placed in the column to overcome the seismic fragility of prefabricated columns effectively. In practical engineering, it is advisable to utilize these columns in regions susceptible to earthquakes and characterized by high seismic intensity levels in order to mitigate the risk of structural damage resulting from ground motion.

The aim of this study is to understand the levels (i.e. mild vs intense) of task conflict (TC) expressions between angel investors and entrepreneurs at the post-investment stage and how it affect angel investors’ follow-on investment intentions with the same entrepreneur.

Survey data was gathered from 71 angel investors in China. Mplus was used to test the proposed research model.

This study found that angels perceive affective conflict (AC) when engaged in intense TC, unlike the case for mild TC expressions. Furthermore, the analysis shows that, unlike mild TC expressions, intense TC expressions impede angels’ reinvestment intentions when they perceive ACs. Other results indicate that when angels perceive that entrepreneurs are not open to coaching, the prominence of mild TC expression is sharply mitigated and becomes as detrimental as intense TC expressions.

This study only focused on one specific aspect of the angel–entrepreneur post-investment relationship: The effect of their TC expressions on angels’ reinvestment intentions. By no means do the authors imply that TC expression in the angel–entrepreneur post-investment relationship is the only factor that matters to angel investors in their follow-on investment intentions with the same entrepreneur.

The findings suggest that entrepreneurs should pay careful attention to TC that may arise between them and their financiers. TCs are not entirely detrimental, but their negative effect might depend on how they are expressed. An appropriate level of TC may also improve enterprise performance and collaboration. Thus, angels and entrepreneurs should set clear goals and performance standards, where task interactions mainly focus on the goals and expected outcomes.

Prior to this study, little was known about whether all TCs potentially lead to ACs. By distinguishing between levels (i.e. mild vs intense) of TC expressions between angels and entrepreneurs, this study adds a novel aspect to it by showing that TC, in and of itself, does not necessarily lead to AC but can lead to AC once its intensity grows.

The work-from-home scheme (WFH) is increasingly being adopted in service firms. However, the blurred border between employees’ work and life can create work–life conflict (WLC) that negatively affects their well-being. Therefore, identifying factors that help employees overcome WLC and nurture their well-being is imperative. From a transformative service research (TSR) and personal psychology perspective, this study aims to explore the roles of service employee state of mindfulness and resilience in reducing WLC, alleviating its negative effects and ultimately nurturing their happiness.

A structural model was proposed. Data were collected from 339 WFH employees in various knowledge-based services such as professional services, information, education and training, financial consulting and marketing. Direct, indirect, mediating and moderating effects were estimated using the CB-SEM method.

Mindfulness is the overarching capability that helps reduce WLC and raise resilience. It nurtures WFH employee happiness not only directly but also via the mediation of resilience and WLC. Resilience, on the other hand, mediates the effect of mindfulness on happiness and moderates the negative impact of WLC on happiness.

Firms are recommended to organize mindfulness and resilience training programs, and encourage organizational- and job-related facilitators. WFH employees should actively participate in such programs and add them to their to-do-list practices.

To the best of the authors’ knowledge, this study is among the first empirical studies of employee mindfulness and resilience in the WFH context. It contributes to the TSR research stream and enriches the concepts of mindfulness and resilience by elucidating different mechanisms in which each of these personal qualities operates to help employees nurture happiness in this specific working condition.

Using sentiment analysis (SA), this study aims to examine the impact of COVID-19 on mental health and virtual learning experiences among 1,125 students at a public Argentinean faculty.

A study was conducted during the COVID-19 pandemic, surveying 1,125 students to gather their opinions. The survey data was analysed using text mining tools and SA. SA was used to extract the students’ emotions, views and feelings computationally and identify co-occurrences and patterns in related words. The study also examines educational policies implemented after the pandemic.

The prevalent emotions expressed in the comments were trust, sadness, anticipation and fear. A combination of trust and fear resulted in submission. Negative comments often included the words “virtual”, “virtual classroom”, “virtual classes” and “professor”. Two significant issues were identified: teachers’ inexperience with virtual classes and inadequate server infrastructure, leading to frequent crashes. The most effective educational policies addressed vital issues related to the “virtual classroom”.

Text mining and SA are valuable tools for decision-making during uncertain times, such as the COVID-19 pandemic. They can also provide insights to recover quality assurance processes at universities impacted by health concerns or external shocks.

The paper makes two main contributions: it conducts a SA to gain insights from comments and analyses the relationship between emotions and sentiments to identify optimal educational policies. The study pioneers exploring the link between emotions, policies and the pandemic at a public university in Argentina. This area of research still needs to be explored.