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This paper aims to investigate the aerodynamic sound generated from flow over bluff bodies at a high Reynolds number. By taking circular and square cylinders as two representative geometries for the cross-section of bluff bodies, this study aims to clarify the difference in flow formation and sound generation between the two types of bluff bodies. Furthermore, the possibility for a downstream flat plate to be used as sound cancellation passive mechanism is also discussed in this study.

Sound source from the near field is numerically solved by using the Unsteady Reynolds-Averaged Navier Stokes equations. While for the sound at far-field, the compact sound theory of Curle’s analogy is used.

Magnitude of the generated sound is dominant by the aerodynamic forcer fluctuations, i.e. lift and drag, where the lift fluctuation gives the strongest influence on the sound generation. The square cylinder emits 4.7 dB higher than the sound emitted from flow over the circular cylinder. This relates to the longer vortex formation length for the case of square cylinder that provides space for more vortex to dissipate. It is suggested that downstream flat plate is possible to be applied for a sound cancellation mechanism for the case of circular cylinder, but it would be more challenging for the case of square cylinder.

This study include implications for the development of noise reduction study especially in high-speed vehicles such as the aircrafts and high-speed trains.

This study identified that there is possible method for sound cancellation in flow over bluff body cases by using passive control method, even in flow at high Reynolds number.

The purpose of this paper is to investigate the human resource factors (rewards, training teamwork and empowerment) that affect service recovery performance (SRP) of customer service employees in life insurances companies. Life insurances industries in Malaysia are facing stiff competitions due to growing consumerism, changing consumer choices and expectations. SRP is very important aspect in the insurances firms toward retaining the customer and one of the key competitive advantages for sustainability and adding value to the organization in the future.

The data obtained from 350 customer service employees based on convenience sampling were analyzed using regression and hierarchical analysis.

There are two factors, namely, empowerment and training, affecting the SRP. The employment status moderated the relationship between reward and SRP. The limitations of this study have been noted and further research suggestions are also included that are very important for SRP.

This study has added knowledge regarding the factors that affect SRP, in general, and precisely in life insurance industries in Malaysian context.