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Aggressive behaviors are common among students. Given the importance of education in reducing aggressive behavior, this study aims to examine the influence of a theory of planned behavior (TPB)-based educational intervention on aggression-preventive behaviors in fifth-grade male students in Fasa city, Iran.

A total of 120 male students were randomly picked from several public schools in Fasa city, Iran, between 2018 and 2019. Assessments were completed before and three months after the intervention. Intervention consisted of eight 55–60-min training sessions based on the TPB’s processes and constructs.

Prior to the educational intervention, there was no significant difference between the two groups in terms of attitude, subjective norms, perceived behavioral control, intention to stop aggressiveness or to engage in aggression-preventive activities. However, three months following the intervention, the experimental group demonstrated a considerable rise in the aforementioned constructs (p > 0.001 in all cases).

The study’s findings demonstrated the efficacy of a TPB-based educational intervention on constructs of the TPB theory. Results suggest application of a TPB-based educational intervention can have a pro-social impact on the attitudes and behavior of elementary age boys.

This study aims to carry out numerical modeling to predict aerodynamic noise radiation from four different Savonius rotor blade profile.

Incompressible unsteady reynolds-averaged navier-stokes (URANS) approach using gamma–theta turbulence model is conducted to obtain the time accurate turbulent flow field. The Ffowcs Williams and Hawkings (FW-H) acoustic analogy formulation is used for noise predictions at optimal tip speed ratio (TSR).

The mean torque and power coefficients are compared with the experimental data and acceptable agreement is observed. The total and Mono+Dipole noise graphs are presented. A discrete tonal component at low frequencies in all graphs is attributed to the blade passing frequency at the given TSR. According to the noise prediction results, Bach type rotor has the lowest level of noise emission. The effect of TSR on the noise level from the Bach rotor is investigated. A direct relation between angular velocity and the noise emission is found.

The savonius rotor is a type of vertical axis wind turbines suited for mounting in the vicinity of residential areas. Also, wind turbines wherein operation are efficient sources of tonal and broadband noises and affect the inhabitable environment adversely. Therefore, the acoustic pollution assessment is essential for the installation of wind turbines in residential areas.

This study aims to investigate the radiated noise level of four common Savonius rotor blade profiles, namely, Bach type, Benesh type, semi-elliptic and conventional. As stated above, numbers of studies exploit the URANS method coupled with the FW-H analogy to predict the aeroacoustics behavior of wind turbines. Therefore, this approach is chosen in this research to deal with the aeroacoustics and aerodynamic calculation of the flow field around the aforementioned Savonius blade profiles. The effect of optimal TSR on the emitted noise and the contribution of thickness, loading and quadrupole sources are of interest in this study.