(Portland, OR)  --  Portland is among the cities and towns across the nation to remember the victims of the September 11th, 2001 terrorist attacks.  A ceremony was held yesterday, the 15th anniversary of the attacks, at the proposed site of a memorial for fallen firefighters.  It's located outside Portland Fire and Rescue Station 21, and would be named after Portland Fire Chief David Campbell, who died in the line of duty in 1911.  Terry Shanley, of the nonprofit David Campbell Memorial Association, tells "The Oregonian" that he's hoping for public support to cover the cost of construction, which is estimated at 750-thousand dollars.