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Transverse Rumble Strips (TRS) acts as safety device that alert inattentive drivers from potential dangers. However, the noise produced due to TRS was reported as noise annoyance among the nearby residents lived adjacent to roadways. Thus, this paper investigates the impulsivity characteristic of noise due to single lightweight vehicles transit on TRS. The objectives of this study are to determine the increase of sound level and to evaluate the impulsivity of noise. Two TRS profiles namely middle overlapped (MO) and middle layer overlapped (MLO) were selected. Three types of single lightweight vehicles which include hatchback, sedan and multipurpose (MPV) were tested at speed of 30, 50 and 70km/h. The sound level was measured using sound level meter (SLM). Noise indices such as LAeq, LAIeqT, LAImax, LAFmax and LASmax were obtained from the measurement. This study considered the differences of LAImax – LAFmax > 2dBA, LAFmax – LAeq ≥ 10dBA, LAIeqT – LAeq ≥ 2dBA and LAImax – LASmax > 6dBA to evaluate the impulsivity of noise. It was found that TRS increased the sound level by at most of 6dBA. Furthermore, all single lightweight vehicles transit on TRS show significant impulsive characteristic. These results proved that TRS produce significant impact to the nearby residents.

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Transverse rumble strips (TRS) are a common choice to reduce vehicle speed and increase driver alertness on roadways. However, there is a potential trade-off using them on rural roadway due to the noise problem created when vehicles go over the strips. The present study investigated the noise level, spectral analysis, and the possible noise generation mechanism when the TRS is hit by a vehicle. Tenraised-rumbler (RR) and three-layer-overlapped (TLO) TRS were selected in this study as they have received complaints from the public. Results showed that RR generated a relatively higher noise and impulse at a low speed, and increased sound level in each octave band. Based on these results, RR may irritate human ears even when the vehicle travels at a low speed. It was found that RR increased all noise generation mechanisms of tyre-pavement interaction whilst TLO increased structural resonance, sidewall and surface texture vibration.

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Abstract. This study was carried out to investigate the effect of beating process to the characteristics of pulp and paper produced from oil palm oil male flower spikes (OPMFS). OPMFS pulp was prepared according to chemical Soda-AQ pulping process. 60 gsm handsheet of oil palm male flower spikes paper were prepared from OPMFS pulp with four different beating times which are 0 revolution, 1000 revolutions, 2000 revolutions and 3000 revolutions. All physical and mechanical characteristics were investigated according to TAPPI and MS ISO standards. The results show that overall physical and mechanical characteristics of POMFS paper were influenced and enhanced by beating process between 0 until 3000 revolutions. This research demonstrate some potential characteristics of palm oil male flower spikes (OPMFS) paper to be investigated as a newly explored non-wood based raw material for papermaking raw material for papermaking.