Dsicussion on modeling an elevator
http://stackoverflow.com/questions/493276/modelling-an-elevator-using-object-oriented-analysis-and-design/12457431#12457431
http://www.cs.cmu.edu/~luluo/Courses/18540PhDreport.pdf
File System
http://pages.cs.wisc.edu/~remzi/OSTEP/file-implementation.pdf
http://stackoverflow.com/questions/5629116/simple-in-memory-file-system
Dsicussion on modeling an elevator zz
原文：http://www.cnblogs.com/majia1949/p/4149058.html