Merge pull request #12 from SMU-SIS/gh-pages

update
Merge pull request #13 from SMU-SIS/gh-pages

update
Merge pull request #14 from SMU-SIS/gh-pages

update
Merge pull request #15 from SMU-SIS/gh-pages

update
practice page fixed
Merge pull request #48 from ruijunhuang2010/gh-pages

modify practice page