I don't think there is a way to prevent dumping of coins once it has been listed on an exchange aside from being a good project itself.

If it is good, then the project should have good prospects of being listed on major exchanges with good liquidity. Paired with good market demand the price should stabilize at initial value, if not more.

I've just seen CoinGecko's 2018 report and they've got some great insights on 2018's ICOs - check out slide 29. https://www.slideshare.net/coingecko/coingecko-2018-full-year-cryptocurrency-report

A good project, even if listed will not dump. The same cannot be said for the rest.