Merge branch 'tim'

Conflicts:
	Makefile
Merge branch 'master' into yzq
Merge branch 'master' into yzq

Conflicts:
	Makefile
	main.bib
Merge branch 'master' into yzq

Conflicts:
	Makefile
	main.bib
修改目录和main.tex
Merge branch 'yzq'