A long-range plan of embankment and afforestation has been propelled at New Tokyo International Airport so that local communities in the sidelines of the runway can recover a quiet and comfortable living environment. Recently, the effectiveness of both the bank and the wood for noise countermeasures was examined from outdoor measurements using real aircraft noise and an artificial sound source. With neither the bank nor the wood being able to be removed, noise measurements without screens were carried out at substitute site locations with source and sound propagation conditions equivalent to those at the bank and the wood. The result of the examination suggests that the bank brings a certain definite amount of sound insertion loss, i.e. approx. 7-12dB at 100m and 6-9dB at 300m behind the bank, at least, under calm or low vector wind conditions. On the other hand, the wood brought sound insertion loss of only 1-2dB. However, a difference of ground surface conditions, which affect sound propagation, between the measurement without the wood and that with the wood prevented definite examination of the effectiveness.

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In recent years, a greater importance has come to be attached to the control of train noise with speedup of train run and increasingly stringent enforcement of environmental criteria. It is found out to be effective in reduction of wheel/rail noise to install acoustic absorptive materials an train track. We developed a new style acoustic absorptive material suitable to install on train track, that is small inorganic particles such as silica bound with small contents of epoxy resin. The development is thought to have good acoustic absorptive properties because it becomes porous structure. To make clear the acoustic absorptive properties of small inorganic bound particles, we examined the influences given by form factors of particles, which mean shapes and mean value and distribution of diameter of particles. As the result we have revealed that the acoustic absorptivity of small inorganic bound particles has great dependencies on particles diameters caused mainly by change of air flow resistance and to get highest acoustic absorptive performance it is demanded to arrange particles diameters in the range from 0.5 to 0.9mm.

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In the recent years, with the increase in high-rise buildings, an increase of high-speed elevators have caused a numerous complains from the dwellers in the rooms located adjacent to the elevator shaft.
For the prediction and control of vibration and structure-borne noise in the room generated by elevator, the basic measurements of noise and vibration were carried out in the high-rise buildings. And in this study, the relationships between the running speed of elevator and noise and vibration, diameter of roller guide and vibration at the guide rail respectively were examined. Furthermore, the authors have focused on the position and detail of guide rail-fastener connections, kinds of guide rail and connections of guide rail, which seem to influence on characteristics of the noise and vibrations, and the relationship between these factors and structure-borne noise and vibrations were clarified.
Finally, based on the further results of examinations, the way reducing the structure-borne noise and vibration generated by elevator and effects of their reduction methods were also discussed.

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