PITTSBURGH — A search engine developed by Carnegie Mellon University researchers will remain a free feature of the City of Pittsburgh's Web site for the long haul.

The search engine Vivisimo.com gives computer users the results of their Web searches clusters grouped together by themes.

Vivisimo has agreed to extend the free service to the city for the long term. The tool can be used to navigate the city's Web site and to search the Internet.

PITTSBURGH — The United Steelworkers union says its new four-year contract with United States Steel Corp. is historic.The deal covers 16,000 workers at 14 domestic plants, including about 2,600 workers at three Pittsburgh-area plants.Workers will receive a $1 hourly raise retroactive to Sept. 1 and a $6,000 lump sum by the end of the month. They'll get 4 percent raises in the last three years of the deal.Steelworkers president Leo Gerard says the deal signals the end of the U.S. steel industry's restructuring and is "historic."

PITTSBURGH — The Carnegie Science Center is planning to expand by 80,000 square feet, build a new sports science exhibition building and create an outdoor "eco park" in the next 10 years.The museum's SportsWorks facility closed last month to make way for a $435 million light rail project. A new SportsWorks is expected to open next August.The science center also is planning a new reception center that would eventually link the main building to SportsWorks. The "eco park" will be next to the main entrance.