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Some of our finest [ about ] Approved Articles (102) Developed Articles (over 900) "I was brought up to believe that the only thing worth doing was to add to the sum of accurate information in the world." —Margaret Mead Draft of the Week [ about ] An internment camp in California Template:Photo Korematsu v. United States was one of four United States Supreme Court cases that dealt with the constitutionality of the Japanese internment during World War II. In its December 18, 1944 decision to uphold the internment, the Court argued forcefully that military necessity legitimates expansive federal government war powers, including those that curtail the civil liberties of specific racial groups. The December 7, 1941 attack by Japan on Pearl Harbor prompted widespread concern about the security of the United States' West Coast and the possibility of espionage by members of its large Japanese-American population. On February 19, 1942, President Franklin D. Roosevelt responded by issuing Executive Order (EO) 9066, which authorized the Secretary of War and his designated commanders to establish "military areas" as they see fit and exclude "any or all persons" from entering or remaining within them. The main result of Roosevelt's order was the relocation of more than 100,000 Americans of Japanese descent from the West Coast into internment camps in the interior of the United States. A month later, Congress passed Public Law 503, which criminalized violations of military orders issued as a result of EO 9066. Persuant to EO 9066, on May 3, 1942, the U.S. army issued Civilian Exclusion Order Number 34, which instructed all persons of Japanese ancestry living in San Leandro, California to evacuate the area by the end of that week. Fred Korematsu, a California-born American citizen whose parents had emigrated from Japan in 1905, refused to comply with the exclusion order. [more...] New Draft of the Week [ about ] Vector rotations are widely used not only in the sciences, such as physics, chemistry and mathematics, but are critical for graphics computations in computer game programs and navigation in space. A typical example used in computer games would be calculating the graphics for a military tank rolling up a slanted hill, the relative rotation of the tank's turret, and the elevation of the tanks' barrel. Although a rotation matrix for each point of the tank could be calculated individually, a more economical method is to calculate a single rotation matrix for the entire tank and apply that solution to every current position of the tank as it rolls up the hill. Additional rotations are then used for the turret rotation by a second multiplication. A variety of methods can be used to determine the rotation matrix (in 3D or 4D space) needed to convert vector V1 into vector V2. Because they provide non-unique results, inverse trigonometry functions should only be used with great caution. Quaternions, a 4-dimensional approach in 3D space, can also be used, and this method has devoted followers and critics. Although several 3D matrix rotation methods can be used, the method of Hughes (J. Graphics Tools, 2000) is particularly fast, because it avoids time-consuming inverse trigonometry and square root calculations, and avoids computational pitfalls of instability inherent to some of the previous methods. [more...]