The provided source material does not contain information regarding a city named Yumi in Papua New Guinea. According to the available documentation, "yumi" is a Japanese term referring to a bow.
In an English context, yumi specifically refers to traditional Japanese asymmetrical bows. These include the longer daikyū and the shorter hankyū, both of which are utilized in the practices of kyūdō and kyūjutsu, the traditional arts of Japanese archery.