Sumida, Tokyo southeast; Taitō to the west; Chūō to the southwest; and Kōtō to the south. The ward was founded on March 15, 1947. It was previously the (ordinary) wards Honjo and Mukojima. Mukojima, formed in 1932, contained the former town of Sumida, which along with the river gave the ward its name. As of 2005, the mayor is Noboru Yamazaki. The council consists of 34 members. Public elementary and middle schools are operated by Sumida. Public high schools are operated by the Tokyo Metropolitan Government Board of Education. In addition, the metropolitan school district also operates a metropolitan junior high school:
Arakawa grids grid cell, e.g., at the grid center or at the grid corners. The Arakawa A-grid is the only unstaggered grid type. The "staggered" Arakawa B-grid separates the evaluation of the two sets of quantities. e.g., one might evaluate velocities at the grid center and masses at grid corners. The "staggered" Arakawa C-grid further separates evaluation of vector quantities compared to the Arakawa B-grid. e.g., instead of evaluating both east-west (u) and north-south (v) velocity components at the grid center, one might evaluate the u components at the centers of the left and right grid faces, and the v components at