Definition - What does Phased Array Technology mean? Ultrasound beams are used in phased array (PA) ultrasonic equipment, which is considered an advanced method of ultrasonic testing. This technology finds applications in medical science and non-destructive testing. This method is more accurate at finding flaws in manufactured materials such as welds.
A migraine is a medical condition which usually causes a pounding, throbbing headache on one side of the head. The pain may be very bad and hurt so much that a person may have a hard time doing anything. While most people who have migraines get a headache, not everyone does.
How to tell you're having a migraine. Nearly 30 million people in the United States have migraines, and three times as many women as men have them. Migraines are pulsating headaches, often on one side of the head. Physical activity may intensify the pain, but symptoms can vary from person to person and from one attack to the next.