This is an advanced implementation of the algorithm described in the following paper:
  J. Zhang and S. Singh. LOAM: Lidar Odometry and Mapping in Real-time.
    Robotics: Science and Systems Conference (RSS). Berkeley, CA, July 2014. 

Modifier: Tong Qin               qintonguav@gmail.com
	  Shaozu Cao 		 saozu.cao@connect.ust.hk

Copyright 2013, Ji Zhang, Carnegie Mellon University
Further contributions copyright (c) 2016, Southwest Research Institute
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