@prefix cpm: . @prefix dc: . @prefix dcat: . @prefix dce: . @prefix dct: . @prefix grg: . @prefix iop: . @prefix ns0: . @prefix ns1: . @prefix owl: . @prefix pav: . @prefix prov: . @prefix puv: . @prefix qudt: . @prefix rdf: . @prefix rdfs: . @prefix reg: . @prefix semapv: . @prefix skos: . @prefix sssom: . @prefix void: . skos:related . skos:member . skos:altLabel "JRC JLN-550" , "JRC JLN-550"@en ; skos:broader , ; skos:definition "A dual-frequency doppler sonar instrument used to provide ship speed information. The lower ultrasonic frequency measures ship speed against ground in deeper waters and the higher frequency measures ship speed against water in shallower depths. The instrument can handle bubble interference generated by high-speed navigation. The transducer is substantially downsized in comparison to conventional instruments, allowing it to be installed on the bow where it will experience less bubble interference. The instrument can measure the ship's fore, aft, port and starboard speeds when combined with GPS information. It comes with a main display and optional wing and remote displays. The JLN-550 operates at 240 kHz (speed against ground) and 2 MHz (speed against water). It measures within speed ranges of -10 to +40 knots within a water depth range of 2-250 m below the hull. It has a speed measuring accuracy of +/- 0.1 knots."@en ; skos:inScheme ; skos:notation "SDN:L22::TOOL1552" ; skos:note "accepted"@en ; skos:prefLabel "Japan Radio Co (JRC) JLN-550 doppler sonar"@en ; skos:related , . skos:related . skos:narrower . skos:related . skos:narrower . skos:narrower . skos:related . skos:narrower .