NEW YORK (AP) -- Two small, struggling television networks, UPN and WB, will merge to form a new network called The CW, executives from them companies that own them said Tuesday. The announcement was made by executives from CBS Corp., which owns UPN, and Warner Bros., a unit of Time Warner Inc., which owns WB. Both UPN and WB had struggled to compete against larger rivals in the broadcast TV business, including Walt Disney Co.'s ABC, News Corp.'s Fox and CBS Corp.'s CBS.