也到南非打高球

今年的世界杯正在南非打得火热,有机会亲历现场观战的人们,自然该对南非有所了解。不知道有机会到南非的朋友们是否知道,这个温暖明媚的海滨国度,不仅是足球的乐园,也是高尔夫球的乐园。南非得天独厚的气候让这里四季都适合打球,全国有大大小小六百个之多的高球场,且依托南非丰富的地理条件,有些在海边,有些在森林中,有些坐落在葡萄酒庄园,还有的背依雄山峻岭,景色绝佳。或许,热爱足球火爆性格的球迷大多并非高球爱家,但到南非打球,绝对是高球爱家们不容错过的。     

Competitive principal component analysis for locally stationarytime series

A new unsupervised algorithm is proposed that performs competitive principal component analysis (PCA) of a time series. A set of expert PCA networks compete, through the mixture of experts (MOE) formalism, on the basis of their ability to reconstruct the original signal. The resulting network finds an optimal projection of the input onto a reduced dimensional space as a function of the input and, hence, of time. As a byproduct, the time series is both segmented and identified according to stationary regions. Examples showing the performance of the algorithm are included