For a typical steel framed 30 ft by 30 ft office building bay, the fre-quency will be in the 5-8 Hz range. Frequency is a function of span (the longer the span, the lower the frequen-cy) and weight supported (the heavier the floor and the supported contents, the lower the frequency).
The following medical conditions are some of the possible causes of Skin color changes. There are likely to be other possible causes, so ask your doctor about your symptoms. 1  Causes of skin whitening:  Vitiligo.
One of the main causes for getting white spots on skin is vitiligo. Melanocytes present in the skin produces melanin, a skin pigment responsible for giving coloration to the skin. If melanin is secreted in less quantity or totally absent it can result in formation of white spots.