Select xml element value which has a namespace in Oracle

I am trying to extract a value from an xml element, located in an XMLTYPE column in an Oracle Table. My Function load_xml return the xml looks something like:

<?xml version="1.0" encoding="utf-8"?>
<ymaps xmlns="http://ift.tt/1nVNXMM" xmlns:xsi="http://ift.tt/ra1lAU" xsi:schemaLocation="     http://ift.tt/1kwHWWc http://ift.tt/1nVO0bn     http://ift.tt/1BjqejM http://ift.tt/1nVNY34     http://ift.tt/1BjqeA9 http://ift.tt/1nVO0bs     http://ift.tt/1BjqeAb http://ift.tt/1BjqeAd     http://ift.tt/1BjqeAf http://ift.tt/1Bjqhfe     http://ift.tt/1nVNY3b http://ift.tt/15VPpxi">
  <Attribution xmlns="http://ift.tt/1nVNY3d"/>
  <GeoObjectCollection>
    <metaDataProperty xmlns="http://ift.tt/WaETtx">
      <GeocoderResponseMetaData xmlns="http://ift.tt/1BjqejM">
        <request>Санкт-Петербург,Кронверкский проспект,27</request>
        <found>1</found>
        <results>10</results>
      </GeocoderResponseMetaData>
    </metaDataProperty>
    <featureMember xmlns="http://ift.tt/WaETtx">
      <GeoObject xmlns="http://ift.tt/1nVNXMM">
        <metaDataProperty xmlns="http://ift.tt/WaETtx">
          <GeocoderMetaData xmlns="http://ift.tt/1BjqejM">
            <kind>house</kind>
            <text>Россия, Санкт-Петербург, Кронверкский проспект, 27</text>
            <precision>exact</precision>
            <AddressDetails xmlns="urn:oasis:names:tc:ciq:xsdschema:xAL:2.0">
              <Country>
                <AddressLine>Санкт-Петербург, Кронверкский проспект, 27</AddressLine>
                <CountryNameCode>RU</CountryNameCode>
                <CountryName>Россия</CountryName>
                <AdministrativeArea>
                  <AdministrativeAreaName>Северо-Западный федеральный округ</AdministrativeAreaName>
                  <SubAdministrativeArea>
                    <SubAdministrativeAreaName>Санкт-Петербург</SubAdministrativeAreaName>
                    <Locality>
                      <LocalityName>Санкт-Петербург</LocalityName>
                      <Thoroughfare>
                        <ThoroughfareName>Кронверкский проспект</ThoroughfareName>
                        <Premise>
                          <PremiseNumber>27</PremiseNumber>
                        </Premise>
                      </Thoroughfare>
                    </Locality>
                  </SubAdministrativeArea>
                </AdministrativeArea>
              </Country>
            </AddressDetails>
          </GeocoderMetaData>
        </metaDataProperty>
        <description xmlns="http://ift.tt/WaETtx">Санкт-Петербург, Россия</description>
        <name xmlns="http://ift.tt/WaETtx">Кронверкский проспект, 27</name>
        <boundedBy xmlns="http://ift.tt/WaETtx">
          <Envelope>
            <lowerCorner>30.309167 59.953241</lowerCorner>
            <upperCorner>30.325624 59.961494</upperCorner>
          </Envelope>
        </boundedBy>
        <Point xmlns="http://ift.tt/WaETtx">
          <pos>30.317395 59.957368</pos>
        </Point>
      </GeoObject>
    </featureMember>
  </GeoObjectCollection>
</ymaps>

I want to extract the content of the "pos" element. But the script below does not output anything.

DECLARE
TEXT CLOB;
POS VARCHAR2(50);
BEGIN
DBMS_OUTPUT.ENABLE;
TEXT := load_xml('http://ift.tt/15VPr8x');
SELECT extractValue(VALUE(t),'/ymaps/GeoObjectCollection/featureMember/GeoObject/Point/pos') INTO POS
FROM TABLE(XMLSequence(XMLType(TEXT))) t;
DBMS_OUTPUT.put_line(POS);
END;
/

Please help me.