To accurately estimate the noise at a signalized intersection, it is necessary to precisely reproduce the traffic volume, signal cycle and traffic noise for each vehicle behavior and driving state. Precise reproduction requires considerable effort, such as continuous calculations of vehicles and the setting of parameters such as engine speed, engine load and velocity. A simple method that involves using A-weighted sound power levels (L WA) under nonsteady running conditions has already been proposed for estimating noise at signalized intersections in a previous paper. In this study, the authors developed two simple methods for predicting noise in which the effects of acceleration and deceleration by signals is reflected. One method is based on a microsimulation traffic model, in which equivalent continuous A-weighted sound pressure levels (L Aeq) is calculated by adding the noise of vehicles passing a green signal and the noise of vehicles decelerating and stopping at a red signal then accelerating when the signal turns green. The other method is even simpler and involves the assumption that an intersection zone is an unsteady running section and that L WA for a nonsteady running section is larger than that for a steady running section. Noise predicting by the three simple methods is compared with actual measurements at 10 sites. The two new methods had slightly improved accuracy relative to the measured results.

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IntroductionIn the ASJ RTN-Model 2003 to predict road traffic noise, a precise computing method of sound propagation is additionally prepared for the situation with complicated boundary condition, and some kinds of spectral model of running vehicle noise are proposed for predictive conditions. In recent Japan, constructions of drainage pavement are being carried out very frequently and widely by the expectation for their noise reduction effect. Therefore, a new prediction method takes account on the condition of drainage pavement. For such a purpose, noise reduction effects on the drainage pavement have been considered, and their simple approximate expressions for numerical calculations could have been obtained. We introduce the circumstances of these considerations and their results as a part of the work establishing the ASJ Mode series.

It is the most important issue for the sustainable society to reduce output as disposal and input of natural resource. This paper shows directions of how to reduce the output from public works and the input for public works.The directions are how to select good ways from various type of recycling. The first is to check from view point of the output of society. The second is to check from view point of the input of society.According to the directions, we found some recycling ways cause increase of the input and/or the output.