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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.

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.

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.

The purpose of this paper is to examine the impact of international remittances on different household welfare indicators including child education, assets, durable goods, and reservation wages of other working age household members. It examines how international remittances are spent for production and consumption by receiving households.

This paper uses fixed‐effect regressions to estimate the impact of international remittances on household spending in Vietnam using Vietnam Household Living Standard Surveys 2006 and 2008.

It is found that most of international remittances are spent on housing and land, debt repayment and saving. A small proportion of remittances are used to buy durable goods. Remittances are not spent in production as well as living consumptions. The effect of international remittances on consumption‐based poverty is very limited.

The findings from this paper suggest that current international remittances are not an effective measure for poverty reduction in the short‐run in Vietnam.

This paper aims to review some effective methods for fully fourth-order nonlinear integral boundary value problems with fractal derivatives.

Boundary value problems arise everywhere in engineering, hence two-scale thermodynamics and fractal calculus have been introduced. Some analytical methods are reviewed, mainly including the variational iteration method, the Ritz method, the homotopy perturbation method, the variational principle and the Taylor series method. An example is given to show the simple solution process and the high accuracy of the solution.

An elemental and heuristic explanation of fractal calculus is given, and the main solution process and merits of each reviewed method are elucidated. The fractal boundary value problem in a fractal space can be approximately converted into a classical one by the two-scale transform.

This paper can be served as a paradigm for various practical applications.

The purpose of this paper is to examine the effects of WebTrust assurance, issued by Certified Public Accountant (CPA) firms, on web purchase behaviour and to examine such effects provided by different‐sized CPA firms.

In an experiment, several scenarios were manipulated to simulate a number of web purchase environments in which participants make decisions online.

The results indicate that the WebTrust assurance seal has a significant effect on consumers' web purchase willingness. An “ordering effect” was also found, in that, removing the seal has more impact than obtaining the seal, and an assurance seal issued by big firms has greater impact than one issued by smaller firms.

This study contributes to the existing literature by focusing on an important yet rarely addressed issue of brand assurance services. The paper helps to understand this phenomenon in a global sense. Compared to the student participants used in the previous literature, this experiment provides a practical addition to the prevalent framework of trust in e‐commerce studies. Finally the research went a further step to test whether the web assurance provided by different‐sized auditors affects web consumers' purchase decisions.

This study aims to identify the ways in which information literacy (IL) in-practice initiatives are framed for Vietnam’s upper secondary students and to suggest an appropriate IL teaching model for schools in the country.

The research used a qualitative multiple case study approach, including two phases of data collection. The first phase gathered data from semi-structured student interviews. The second phase included semi-structured professional interviews and an analysis of documents.

The research found that time pressure, teaching method, resource issues, students’ awareness of IL and support from family are challenges for the development of IL programmes. These factors impinge upon the development of an IL teaching model for Vietnam’s upper secondary schools.

The focus of this study was limited to two schools to gain the depth of data needed to provide a holistic picture of the practice of IL teaching in Vietnam’s upper secondary schools.

This study could provide some guidance to the Ministry of Education and Training in the development of educational policies and initiatives through identifying the possible contributions of IL to Vietnam’s education system.

The study provides an understanding of the development of IL in the education system in transition, from a didactic to a constructivist approach.