单词	矿难
释义	矿难 KuàngNànmine disaster繁体礦難
随便看	directivity index of a sound source directivity index of microphone directivity index of telephone transmitter directivity directivity angle directivity characteristic directivity coefficient directivity deviation directivity diagram directivity diagram laser directivity of a microphone directivity of an antenna directivity of antenna directivity of loudspeaker directivity on horizontal plane directivity on vertical plane directivity pattern directivity pattern diagram directivity pattern testing directivity response pattern directivity separation Directivity sharpening directivity signal directivty directiy heated cathode