A Study on the Seasonal Fluctuation Model for Municipal Solid Waste and its Irregular Component
Akira Koizumi* and Yasuhiro Arai*
* Graduate School of Engineering, Tokyo Metropolitan University
õ Correspondence should be addressed to Yasuhiro Arai:
Department of Civil Engineering, Tokyo Metropolitan University
i1-1 Minamiosawa, Hachioji, Tokyo, 192-0397 Japanj
Abstract
The purpose of this study is to develop a seasonal fluctuation model using information from a time series analysis on the collection amount of municipal solid waste. In this study, we make an analysis of seasonal fluctuation to show the relationship between the irregular component in a time series and the scale of waste collection amount.
Firstly, we defined the cyclical, seasonal, and irregular components in a time series, and developed a seasonal fluctuation model with a finite Fourier series. Secondly, we examined the data size required for an application of the model to consider the effect of temporal changes on the components of the model. It was shown that the model application required a period of more than five years for an adequate data size. The abstraction of the seasonal component was then not affected by the data period. Thirdly, in order to determine the quantitative characteristics of the component composition, we used the contributory ratio Īk that is calculated from the square of the amplitude Xk.
Lastly, we applied the model to data on household and commercial waste in several cities. It was found that the irregular component propotion decreases as the amount of the waste collection increases.
Key words: collection amount of municipal solid waste, seasonal fluctuation model,
finite Fourier series, irregular component, time series data