Which country has doosan infracore as then company name?
CREATE TABLE "manufacturer_s_worldwide_ranking" (
  "rank" real,
  "company_name" text,
  "2008_rank" text,
  "2009_revenue" text,
  "north_american_brands" text,
  "world_headquarters" text,
  "country" text
);
SELECT "country" FROM "manufacturer_s_worldwide_ranking" WHERE "company_name"='Doosan Infracore';