in this paper, we propose a new residual analysis method using fourier series transform into fuzzy time series model for improving the forecasting performance. this hybrid model takes advantage of the high predictable power of fuzzy time series model and fourier series transform to fit the estimated residuals into frequency spectra, select the low-frequency terms, filter out high-frequency term...

sulfur dioxide has two important sources in the atmosphere and this is why most of scientists believe in a geographic split in the globe. power plants, major emitter of so2, are located in north hemisphere such as in russia, china, canada and the usa. in south hemisphere, phytoplankton produces a massive amount of dimethyl sulfide (dms) and dimethyl disulfide (dmds). then these types of reduced...

clustering is one of the known techniques in the field of data mining where data with similar properties is within the set of categories. k-means algorithm is one the simplest clustering algorithms which have disadvantages sensitive to initial values of the clusters and converging to the local optimum. in recent years, several algorithms are provided based on evolutionary algorithms for cluster...

the renewable energy resources such as wind power have recently attracted more researchers’ attention. it is mainly due to the aggressive energy consumption, high pollution and cost of fossil fuels. in this era, the future fluctuations of these time series should be predicted to increase the reliability of the power network. in this paper, the dynamic characteristics and short-term predictabili...

water quality is a worldwide problem which affects human beings lives fundamentally. water scarcity is intensified in result of quality deterioration. different factors such as population increase, economic development and water pollution could be considered as the origins of the problem. the study and forecasting of water quality is necessary to prevent serious water quality deteriorations in ...

the sales proceeds are the most important factors for keeping alive profitable companies. so sales and budget sales are considered as important parameters influencing all other decision variables in an organization. therefore, poor forecasting can lead to great loses in organization caused by inaccurate and non-comprehensive production and human resource planning. in this research a coherent so...