Anybody ever watch "The Dog Whisperer" on National Geographic? It really helps you understand the mentality of dogs.

Anyway, just as you go by, don't make eye contact. Also stay confident and make yourself be in charge of the situation. Even if you're in their territory, they won't attack unless they sense you are weak. If they're coming and you can't get away, stand firm, stick your chest out and shout. You can say "NO." It doesn't really matter so long as you say it in a assertive tone. You have to try and get the dog's mind startled. Which is why spraying them with water works, too. It knocks their brain out of that mode. Kinda like when walking and correcting with a leash.

If it's a dog you can over-power, try and grab them by the neck and slam them to the ground. It's what their pack leader would do to them. And if dogs are trying to jump on you, don't let them. Ignore them. They are trying to dominate you.

Just tell yourself in you mind that you have it under control, and you can probably deter them.