see strength of materialsstrength of materials, measurement in engineering of the capacity of metal, wood, concrete, and other materials to withstand stress and strain. Stress is the internal force exerted by one part of an elastic body upon the adjoining part, and strain is the deformation or change in. ..... Click the link for more information.
The Koreans are believed to have originated from ancient China. This is gathered from the archaeological and linguist evidence.
Koreans mainly live in the two Korean nation states, South Korea and North Korea (collectively referred to simply as Korea), but are also an officially recognized minority in China, Vietnam, Japan and Philippines, plus a number of former Soviet states, such as Russia and Uzbekistan.