Brushless Doubly Fed Machines (BDFM) have potential advantages in variable
speed generation and adjustable speed drive applications. The most significant of these
advantages is a reduction in the power electronic converter rating, and therefore a
reduction in overall system cost. Presently, efforts are being directed at optimizing the
design of...
Pollution prevention is promoted by the Environmental Protection Agency (EPA) and other governmental agencies as a method of reducing the generation of wastes and pollutants. Pollution prevention is also called source reduction because it reduces wastes early in the production process. Source reduction has been used by some industries to...
Blue whales (Balaenoptera musculus) are the largest of the baleen
whales. Blue whale calls were recorded off the coast of California in fall,
1993 and measured for frequency and time characteristics. On average, blue
whale calls lasted 16 s, swept down from 18.9 to 17.3 Hz and were
repeated every...
Grape phylloxera, Daktulosp/iaira vitfoliae (Fitch) development was studied under field and laboratory conditions. The aphid-like insect feeds on Vitis vinfera L. roots producing swellings that decay and lead to vine decline. The only long-term economic solution for control of grape phylloxera (GP) is to plant vines grafted onto a resistant...