This train is called NANOHANA.
Many tourists uses this train to go to Ibusuki City, the southern resort.
The color of the train is yellow.
The yellow color derives from the symbol flower of Ibusuki City. The Japanese name of the flower is NANOHANA. Its formal name is the rapeseed blossom.
The flower opens in January and February in Winter.
How long it takes to Ibusuki city?
The rapid train NANOHANA DX connects Kagoshima City and Ibusuki City in 55 minutes.
The fare is about 940 yen (as of 12 April 2015).
There are also rapid express TAMATEBAKO. TAMATEBAKO is very fast but the fare is twice as expensive as NANOHANA DX.
So, I recommend you to take NANOHANA if you want to enjoy beautiful scenery from the train.