Regarding the SovietĀ  efforts to produce, through artificial selection, tamed versions of the Silver Fox, is it possible to generalise, based on the genetic differences between domesticated Silver Fox and wild ones as well as the procedures used to tame them, how this rate compares to that of natural selection of proto-dogs? Similarly, if one were to attempt to use regimes of artificial selection on various primate populations, could we come up with a reasonable estimate for how long it would take to breed human-level intelligence?

Are there any other known research projects involving artificial selection with similarly ambitious ends?

That is a great example, the silver fox story. I use it often as an example of the power of natural selection as an explanatory tool for what we observe around us.

The first thing we should point out is that the example is only a model of the situation which we are hypothesising about, namely the original domestication of dogs from wolves, or something similar. You probably can extrapolate the result from one to the other, with a couple of caveats.

Starting from a different species of canine or even a different population of the same species could produce different rates of evolution, in terms of how long it takes to acheive the desired state. Would a wolf population take longer to domesticate then foxes or dingos?

Second, you have to assume that the selection pressures are similar enough to your hypothetical situation to warrent direct comparison. For example, the foxes in captivity would have been released from certain pressures, like predators and searching for shelter. Depending on the trait selected for, the process may be delayed by conflicting pressures in the hypothetical, uncontrolled envrionment.

I have no particular reason why the same concept for intelligence in chimps shouldn't work, although I suspect that because the timescales involved would be so much longer and the end point so much fuzzier, the experiment might prove a little too difficult to be practical.

I think the greatest achievement in recent times using artificial selection is Craig Venter and his artificial genome. Every step in that process involved selecting a cell that performed the correct job by careful manipulation of the environment.