By way of the ppf curve a shift inward is displayed. What would the technological change be?

Since this is not my area of expertise, I searched Google under the key words "ppf" to get these possible sources:

http://en.wikipedia.org/wiki/Production_possibility_frontier
http://www.netmba.com/econ/micro/production/possibility/

Since you don't define which "ppf" you want, it is hard to know if my answer is helpful. If not, please repost with more specific information. Thanks for asking.