I do not think that a bear's reaction to a barking dog would necessarily be fear. Whether or not a bear confronted by a dog would leave the scene would depend on other factors, including the bear's personality and its past experience with campsites.

It is also worthwhile to contemplate whether the dog confronted by a bear would continue to bark and stand its ground, or react with fear. This, too, would be subject to the personality of the dog and its past experience.

It does not sound like a reliable bear deterrent system to me.

NB: This is not "offical", but merely how it strikes me.