This website is based on the design principle of accessibility and uses keyboard shortcuts to strengthen the browsing convenience Layout is divided in 3 areas：
1. the main menu zone at the top、2. the content zone at the center、3. the related information zone at the bottom
The following keys are set as the Access keys ( or speed keys) of this website.
Alt+U：Upper block, containing the links to the services of this site, search box, font size setting and versions of this site.
Alt+C：Main content area shows the content of each page.
Alt+Z：Block the link below, this website links and other contact information and so on.
Alt+S：Website Search.