DDPG 개념1
https://ropiens.tistory.com/96
DDPG 개념2
https://velog.io/@kjb0531/DDPG
DDPG 개념3
https://lynnn.tistory.com/75
DDPG TORCS 차량 센서값 부분
https://github.com/djo10/deep-rl-ddpg-self-driving-car/blob/master/gym_torcs.py
DDPG ROS 참고 부분
https://github.com/m5823779/motion-planner-reinforcement-learning
DDPG wiki
http://wiki.hash.kr/index.php/DDPG