<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31304577</termId><termName>sonar</termName><termType>PT</termType><termNote><![CDATA[ A method of detecting the presence of objects under water by means of sonic and ultrasonic waves that are reflected from the object. ]]></termNote><termCreatedDate>2026-03-30 20:21:55</termCreatedDate><relation><relationType>UF</relationType><termId>31304578</termId><termName>anti-submarine detection investigation committee</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31304579</termId><termName>asdic</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31304580</termId><termName>echo ranging</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31304581</termId><termName>echo sounding</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31304582</termId><termName>ranging, echo</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31304583</termId><termName>sound navigation ranging</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31304584</termId><termName>sounding, echo</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31298668</termId><termName>exploring and investigating techniques</termName><termType>PT</termType></relation></term>  </Zthes>