This chapter is from the book The Electrical Engineering Handbook: CRCnetBASE, which is a comprehensive compilation of physical, chemical, material, and mathematical data, encompassing the entire field of electrical engineering. The CD-ROM includes definitions and explanations of nearly 2,000 terms; almost 3,500 equations and formulas, more than 2,000 figures, and 200 tables; software application chapters in each section; extensive bibliographic references; and complete descriptions of applicable U.S. and international professional societies and associations.