To adjust timezone on your Linux to Pacific Standard Time (PST/PDT), type the following on command line.
sudo mv /etc/localtime /etc/localtime.org; sudo ln -s /usr/share/zoneinfo/America/Los_Angeles /etc/localtime
To adjust timezone on your Linux to Japanese Standard Time (JST), type the following on command line.
sudo mv /etc/localtime /etc/localtime.org; sudo ln -s /usr/share/zoneinfo/Asia/Tokyo /etc/localtime