direction ray目标射线directionn.方向；指导；用法说明；趋势；目标；管理directional-type tricone bit定向型三牙轮钻头Direction of hospital customer医院顾客导向directional wavelet transforms方向小波direction measurement locating测向定位directional partial derivative方向偏导数directional drilling technique定向钻进技术directional multi-resolution方向多分辨direction of striking position拳式方位directional tracking precision定向跟踪精度directional blasting technique定向爆破技术