CAPACITOR = "http://purl.org/ee/part-type#capacitor"
RESISTOR = "http://purl.org/ee/part-type#resistor"
DIODE = "http://purl.org/ee/part-type#diode"
INDUCTOR = "http://purl.org/ee/part-type#inductor"
CRYSTAL = "http://purl.org/ee/part-type#inductor"