Sahand,
What a thought provoking question! If I had all of my knowledge and expertise and could travel back in time to Sunday April 14, 1912, a few hours prior to Titanic hitting the iceberg, I am not sure I would try to save the ship. A TV Series that came out in the 60's called 'The Time Tunnel' covered this very subject. Whether to save the ship or let her sink.
This one act would alter history in such a major way. One does not know if they would have ever been born if Titanic had not sank. This gets us into the 'what if' scenario.
If I could account and answer all of the 'what if's....' then my answer would be yes I would try to save the ship. If the opportunity arose I would go to Lightoller first off. I would give him the exact position of the 'berg' and try to convince him to change course. If that failed, I would try the captain, then Murdoch and anyone else that would listen.
Here are some what if's you can try to answer:
1) If the Titanic had not sank, then Cal Archibald Gracie would not have died in Dec 1912. What effect would that have had?
2) Same as above, but JJ Astor would have remained alive, to probably live out a full life.
3) J. Bruce Ismay would not have been vilified, so with his growing power in IMM, what effect would that have had on American commerce?
Do you see what I mean. To many very powerful people died on titanic, and had they have lived to there fullest potential, what changes in the world would have come? Would the stock market crash of 1929 even happened? Lastly, what would life be like now if the Edwardian Era or Gilded Age had continued?