In advanced countries, various policies are being enforced to reduce equipment noise level at it’s source. This paper analyses the problems of domestic noise policies related to noisy equipment, and presents a plan for improving the implementation of expansion policy of low noise equipment based on this analysis. This paper proposes that the equipment satisfying the compulsory rule be able to use the environmental certification mark, the standards of which are defined in recommended rules, to improve the linkage between the two policy measures. This paper also suggests expanding the range of equipment to be supervised and using new noise label that has grades and shows detailed noise level of the equipment to improve environmental certification system. In addition, supplementing the construction permission system and supporting international certification system are offered to expand the use of low noise equipment.
PURPOSES: The purpose of this study is about noise which is generated from roads and is consist of irregular frequency variation from low frequency to various band. The existing methods of noise reduction are sound barrier that uses insulation material and absorbing material or have applied passive technology of noise reduction by devices. The total frequency band is needed to apply active noise control.
METHODS: In this study applies to the field of road traffic environment, signal processing controller and various analog signal input/output, the amplifier module is based on parallel-core embedded processor designed. DSP performs the control algorithm of the road traffic noise. Noise sources in the open space performance of evaluation were applied. In this study, controller of active signal processor was designed based on the module of audio input/output and main controller of embedded process. The controller of active signal processor operates noise reduction algorithm and performance tests of noise reduction in inside and outside environment were executed.
RESULTS : The signal processing controller with OMAP-L137 parallel-core processors as the center, DSP processors in the active control operations dealt with quickly. To maximize the operation speed of an object and ARM processor is external function keys and display for functions and evaluating the performance management system was designed for the purpose of the interface. Therefore the reduction of road traffic noise has established an electronic controller-based noise reduction.
CONCLUSIONS : It is shown that noise reduction is effective in the case of pour tonal sound and complex tonal sound below 500Hz by appling to Fx-LMS.