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The purpose of this paper is to carry out a set of micromechanical analyses to study the effect of small inclusions on fatigue life of wind turbine bearings.

The local stress concentrations around an inclusion are determined from a characteristic unit cell model containing a single inclusion, using the approximation of a 2D plane strain numerical analysis. The Dang Van multiaxial fatigue criterion is used for the local stresses in the matrix material, to ensure that the stresses remain within the fatigue limit. The matrix material is taken to be one of the most commonly used bearing steels, AISI 52100, and two different types of inclusions are considered. The macroscopic stress histories applied correspond to either a Hertzian or an elastohydrodynamic (EHL) contact pressure distribution under the rollers.

The paper shows that sub-surface fatigue failure due to rolling contact is more likely to develop close to the inclusion-matrix interface, at particular angles that depend on the material and on the inclusion orientation.

Inclusions represent an important issue in the design of wind turbine bearings, that are supposed to work in the very high cycle regime (N>109 cycles). This paper develops a micromechanical study that provides a deeper understanding on effect of inclusions on the fatigue life, according to one of the most used multiaxial fatigue criteria.

This study aims to investigate aspects related to the changing trends of the rainfall extremes in the entire Mekong Delta in the period of 32 years (1984-2015) applying rainfall extreme indices. First, the homogeneity tests were applied to assess the quality of observed rainfall data series. The authors, then, investigated three rainfall indices including the number of very heavy rainfall days 20 mm (R20), number of days above 50 mm (R50) and number of days above 100 mm (R100) applying the Mann-Kendall test and Sen’s slope estimate.

First, the homogeneity tests were applied to assess the quality of observed rainfall data series. The authors, then, investigated three rainfall indices including the number of very heavy rainfall days 20 mm (R20), number of days above 50 mm (R50) and number of days above 100 mm (R100) applying the Mann-Kendall test and Sen’s slope estimate.

The results of R20 pointed out that an insignificant upward tendency was found in the coastal provinces, whereas an insignificant downward tendency was also recorded in the inland provinces. Regarding the number of R50, a similar trend to R20 was recorded with five stations slightly increased and five stations slightly decreased. For the number of R100, the results recorded an absence of significant trends over the entire study area. Approximately 58.5% of stations show a slightly decreasing trend, while 41.5% of the remaining stations recorded a slightly increasing trend.

For the number of R100, the results recorded an absence of the significant trends over the entire study area. Approximately 58.5% of stations show a slightly decreasing trend, while 41.5% of the remaining stations recorded a slightly increasing trend. Of note is the fact that the number of R100 occurred more frequently in the northern provinces, which means the northern region is facing a high risk of flooding.

This study aims to investigate the institutional, macroeconomic and firm-specific determinants of financial leverage in Vietnam and provides new evidence from the dynamic panel fractional estimator.

This study uses a panel dataset of 859 Vietnamese firms from 2008 to 2022 and employs three estimators: Feasible Generalized Least Squares (FGLS), System Generalized Method of Moments (SysGMM) and Dynamic Panel Fractional (DPF), with DPF being particularly suitable for handling fractional dependent variables and the dynamic nature of financial leverage.

The results confirm the dynamic nature of the financial leverage model, with firm-specific factors, institutional factors and macroeconomic factors playing significant roles in shaping firms' financing decisions. The DPF estimator highlights the positive impact of stock market development on leverage. This study contributes to the literature by providing new evidence on the determinants of leverage in Vietnam, using the DPF estimator for more accurate estimation and revealing the significant impact of the size of the banking sector, the size of the stock market, the stock market development index, the financial development index and the corruption perception index on leverage.

This study contributes to the literature by providing new evidence on the dynamic nature of the financial leverage model and the impact of institutional, macroeconomic and firm-specific factors on financial leverage in the context of Vietnam. The use of the DPF estimator allows for a more accurate and reliable estimation of the determinants of leverage, considering the fractional nature of the dependent variable and the persistence of capital structure decisions over time.

This study aimed to utilize Epistemic Network Analysis (ENA) for a thorough evaluation of policy documents concerning the digital transformation in Vietnam's higher education sector.

Adopting a quantitative ethnography approach, this research employed ENA to analyse a curated collection of 21 documents that specifically addressed higher education (HE) and digital transformation within Vietnam. The study also incorporated qualitative content analysis, utilizing the constant comparison method as outlined by Onwuegbuzie et al. (2009), for data coding. ENA facilitated the examination of connections among various policy aspects.

The study revealed a consistent overarching theme in Vietnam's digital transformation policies during and post-pandemic, focusing on key areas such as ADMINISTRATION, VISION, QUALITY, and INFRASTRUCTURE. However, a temporal shift in emphasis was observed: during the pandemic, policies were more focused on ADMINISTRATION and INFRASTRUCTURE, while post-pandemic, there was an increased emphasis on COLLAB, VISION, and TEACH_LEARN.

This research represents one of the initial efforts to showcase the utility and significance of ENA in analysing policy documents. It underscores ENA's potential in elucidating the complex interplay of policy elements in the context of digital transformation in higher education, particularly within a developing country setting.

The purpose of this study is to evaluate the rainfall intensities and their limits for durations from 0.25 to 8 h with return periods from 2 to 100 years for Ca Mau City in Vietnam.

First, the quality of the historical rainfall data series in 44 years (1975–2018) at Ca Mau station was assessed using the standard normal homogeneity test and the Pettitt test. Second, the appraised rainfall data series are used to establish the rainfall intensity-duration-frequency curve for the study area.

Based on the findings, a two-year return period, the extreme rainfall intensities (ERIs) ranged from 9.1 mm/h for 8 h rainstorms to 91.2 mm/h for 0.25 h. At a 100-year return period, the ERIs ranged from 18.4 mm/h for 8 h rainstorms to 185.8 mm/h for 0.25 h. The results also show that the narrowest uncertainty level between the lower and upper limits recorded 1.6 mm at 8 h for the two-year return period while the widest range is at 42.5 mm at 0.25 h for the 100-year return period. In general, the possibility of high-intensity rainfall values compared to the extreme rainfall intensities is approximately 2.0% at the 100-year return period.

The results of the rainfall IDF curves can provide useful information for policymakers to make the right decisions in controlling and minimizing flooding in the study area.

This study aims to investigate the role of self-esteem in mediating the relationship between passive social networking usage (PSNU) and life satisfaction, as well as whether the relationships between PSNU and self-esteem/life satisfaction as well as self-esteem and life satisfaction vary by gender.

This research is conducted in compliance with the ethical standards of the American Psychological Association’s study on a subject of 304 students. Study participants are invited to participate in the survey by completing the anonymous questionnaire regarding passive social network usage, self-esteem and life satisfaction.

The findings indicate that self-esteem mediated the relationship between PSNU and life satisfaction. Furthermore, gender moderated the self-esteem and life satisfaction relationship, and such an effect was stronger for females than males.

This study, adopting a cross-sectional design and self-report scale, examined the relationship between PSNU and life satisfaction. However, the short study duration hindered establishing a cause-and-effect relationship. Credibility concerns arose from participant-induced noise variables in the self-report scale. Future research should use diverse methods to validate underlying mechanisms. Despite limitations, the study revealed self-esteem as a mediating factor, alleviating the negative impact of PSNU on life satisfaction. Both male and female users are encouraged to engage in self-education, valuing their self-esteem for heightened life satisfaction.

These findings contribute to the understanding of how passive social network usage predicts life satisfaction (mediating effect of self-esteem) based on social comparison theory and when self-esteem increases life satisfaction (moderating effect of gender) based on social role theory of gender differences.

This study aims to investigate how two different types of brand-to-brand dialogues – “roasting” versus “toasting” – impact consumers’ brand perceptions, particularly perceived entertainment, and influence brand attitudes.

The research design comprises four studies. The preliminary study involves Web scraping to gauge consumer perception about the two communication approaches followed by two well-known brands. Study 1 involves an online experiment to compare these communication types within each brand tested in the pilot study and examines the mediation effect of perceived entertainment. Study 2, also an online experiment, investigates the role of message neutralization, demonstrating that “roasting” can be acceptable when the humor is neutralized. Study 3 further tests the effects of neutralized “roasting” at different levels of brand familiarity and personality.

Roasting can lead to more favorable consumer perceptions than toasting. The effect can be explained by roasting’s higher level of perceived entertainment. However, this positive outcome is contingent on the successful neutralization of the aggressive humor in the “roasting” messages. When it comes to brand familiarity and personality, familiar brands benefit more from neutralized “roasting,” whereas brand personality does not have a strong influence.

The findings suggest that “roasting” can be effective when messages are neutralized, and “toasting” works best when spontaneous and genuine. It highlights how brand familiarity and personality influence consumer reactions, thus, offering strategic insights for both established and lesser-known brands. The study also prompts further research to examine other brand traits, cultural factors and behavioral dimensions in brand-to-brand dialogue, signifying the complexity and richness of this growing research area.

This study advises lesser-known brands to adopt “toasting” strategies to build a positive image, while established brands can try “roasting,” ensuring message neutrality to avoid negativity. The research emphasizes the role of brand familiarity and personality in shaping brand dialogues. Marketers must consider these to make humor strategies effective and bolster positive brand image.

This research uniquely examines message neutralization through contextual cues as a strategy brands can use to aid their sensitive dialogues with others on social media. The findings provide new insights into how brands can use different types of messages in digital communications to attract consumers and ensure positive reception, offering valuable guidance for academics and practitioners in brand-to-brand dialogue.

Academic buoyancy refers to a student’s adaptive response to overcome common academic-related stress and challenges. Guided by social cognitive theory, we investigated the relation between students' academic buoyancy and their endorsement of compassionate and uncompassionate self-responding.

Students from a Minority-serving, Hispanic-serving public university (N = 112) completed an online survey assessing academic buoyancy (Martin and Marsh, 2008) and self-compassion (Neff, 2003). We conducted a hierarchical regression analysis with uncompassionate and compassionate self-responding as predictors and academic buoyancy as the outcome.

Compassionate self-responding (i.e. self-kindness, common humanity and mindfulness) explained additional variance above and beyond what uncompassionate self-responding (i.e. self-judgment, isolation and overidentification) explained in the model. Uncompassionate self-responding components emerged as the strongest predictors of academic buoyancy.

Limited research exists regarding the relation between self-compassion and academic buoyancy, especially in the higher education setting. This research indicates that student compassionate self-responding is associated with students’ adaptive response to overcoming academic setbacks, stress and challenges. The findings of the current research could have meaningful implications for university officials’ efforts in helping students overcome academic-related setbacks and achieve academic success in higher education. University offices, programs and communities can focus on compassionate self-responding to support students in overcoming common school-related setbacks. Programs could be developed to move students away from uncompassionate self-responding as a means of promoting buoyancy.

Data crawling in e-commerce for market research often come with the risk of poor authenticity due to modification attacks. The purpose of this paper is to propose a novel data authentication model for such systems.

The data modification problem requires careful examinations in which the data are re-collected to verify their reliability by overlapping the two datasets. This approach is to use different anomaly detection techniques to determine which data are potential for frauds and to be re-collected. The paper also proposes a data selection model using their weights of importance in addition to anomaly detection. The target is to significantly reduce the amount of data in need of verification, but still guarantee that they achieve their high authenticity. Empirical experiments are conducted with real-world datasets to evaluate the efficiency of the proposed scheme.

The authors examine several techniques for detecting anomalies in the data of users and products, which give the accuracy of 80 per cent approximately. The integration with the weight selection model is also proved to be able to detect more than 80 per cent of the existing fraudulent ones while being careful not to accidentally include ones which are not, especially when the proportion of frauds is high.

With the rapid development of e-commerce fields, fraud detection on their data, as well as in Web crawling systems is new and necessary for research. This paper contributes a novel approach in crawling systems data authentication problem which has not been studied much.

As humans are influenced by their environment, this study explores how different construal levels of ambient scent temperature affect consumers’ food choices.

This study employed a series of experimental methods from three studies, totalling five experiments. The experiments involved both laboratory and field settings, as well as neuroscientific techniques, thus generating empirical evidence.

Three studies were conducted to investigate how construal levels of both ambient scent temperature and tasks influenced food choice. Study 1 found that the construal level of ambient scent temperature significantly affected the type of food consumed. Study 2 included the task’s construal level as another factor to examine whether it interacted with the ambient scent temperature construal level. Both factors were significant, but only when perceived by the participants simultaneously. If the task’s construal level was manipulated before exposure to the ambient scent temperature, the latter did not have a significant effect. Study 3 employed a neuroscientific method to explore the mechanism behind the match between ambient scent temperature and food choices based on construal levels. The congruence of ambient scent temperature and food choice based on construal level enhanced positive emotions.

The sample size, although in line with other neuroscientific studies, was not sufficiently large for robust generalizability. This limitation can encourage future research to increase the number of participants and thus enhance the accountability of the findings. Another limitation is the participants’ cultural background.

This study’s practical implications are twofold. First, odour intensity was perceived to be the strongest in hot samples (Kähkönen et al., 1995), and we confirmed how ambient scent temperature can influence one’s food choice. Thus, food business operators can use warm ambient scent temperatures to promote hedonic food or snacks. Second, participants’ positive emotions were enhanced by the congruence of ambient scent temperature and food choice.

The association between ambient scent temperature and food choice has been extensively researched. However, this study provides an empirical explanation for the application of CLT. Accordingly, we performed a series of laboratory and field experiments using behavioural and neuroscientific approaches. The results confirmed that the construal level of ambient scent temperature significantly affected food choice. Moreover, the FAA revealed that one’s positive emotions would be prompted if there was congruence in the construal levels of ambient scent temperature and food choice.

This study has theoretical and managerial value because people’s poor understanding of food selection is affected by ambient scent temperature. Moreover, its novelty lies in the application of a neuroscientific approach to one experiment.